Comprehensive Description
provided by Smithsonian Contributions to Zoology
Orconectes pellucidus (Tellkampf)
Krebse.—Anonymous, 1843a:49.
Astacus Bartoni?.—Anonymous [not Fabricius], 1843b: 175.—Putnam [not Fabricius], 1872:10.
Astacus pellucidus Tellkampf, 1844a:684; 1844b:383.—Thompson, 1844:111.—Tellkampf, 1845:85, 93.—Erichson, 1846:87, 89, 95.—Gibbes, 1850:195.—Dana, 1852: 522.—Newport, 1855:164.—Lucas, 1864:iv.—Hagen, 1870:6, 7, 11, 55.—Smith, 1873:639.—Faxon, 1885a:10.—Rhoades, 1944:112; 1959:399.
Astacus (Cambarus) pellucidus.—Erichson, 1846:95, 96.—Rabé, 1890:9.
Craw-fish.—Silliman, 1851:336.
Cambarus pellucidus.—Girard, 1852:87, 88.—Hagen, 1870: 8, 27, 30, 31, 32, 33, 34, 55, 56, 97, 101, pl. 1, figs. 68–71, pl. 3, fig. 148, pl. 6.—Packard, 1871:750, 751, fig. 131.—Cope, 1872a: 410, 419.—Packard, 1872b:17, 18, fig. 131.—Hagen, 1872:494, 495.—Packard, 1873:94.—Smith, 1873:639 [in part].—Packard, 1874:209.—Putnam, 1875a:222; 1875b:191, 198.—Smith, 1875:477 [in part].—Putnam, 1877:16–19.—Packard, 1879:315, 316, 317, figs. 268, 269.—Hubbard, 1880:38.—Leydig, 1883: 38, 39, 40.—Faxon, 1884:139, 140 [in part]; 1885a:4, 5, 7, 8, 9, 11, 16, 18, 19, 40, 41, 42, 43, 44, 45, 46, 59, 82, 83, 84, 111, 158, 169, 174, 178, 179 [in part]; 1885b:358.—Underwood, 1886:371 [in part].—Packard, 1888:8, 10, 12, 19, 24, 110, 111, 112, 119, 122, 123, 125, 127 [in part].—Garman, 1889:235, 236.—Faxon, 1890:626, 628.—Packard, 1890:393 [in part].—Parker, 1890:153, 154, 155, 157–161, pl. 1, figs. 2, 3, 4, 5, 6.—Hovey, 1891:72.—Ortmann, 1892:11 [in part].—Cunningham, 1893:537.—Stebbing, 1893:208.—Lönnberg, 1894:126; 1895:4–6, 9.—Hay, 1896:485 [in part].—Call, 1897: 103, 104.—Hay, 1897: 208 [in part].—Faxon, 1898:647 [in part].—Eigenmann, 1899:60.—Hay, 1899:959, 966 [in part].—Call, 1901: 103, 104.—Ortmann, 1902:227, 278, 279 [in part].—Hay, 1902a:226, 228, 230, 232, 234, 235 [in part]; 19026:436.—Steele, 1902:7, 16, 18 [in part].—Eigenman, 1903:169 [in part].—Harris, 1903a:602, 606; 1903b:58, 67, 70, 80, 112–118, 151, 153, 157, 162, 167 [in part].—Ortmann, 1905a:92, 95, 96, 97 [in part].—Bell, 1906:300, 304, 305.—Banta, 1907: 6, 59, 70, 71, 72, 73, 102, 103 [in part].—Graeter, 1909:470 [in part].—Pearse, 1910:10.—Hovey, 1912:80, 81, 108, 109, 115, 119, 124, 2 figs.—Osborn, 1912:923 [in part].—Faxon, 1914:415, pl. 7, fig. 2a-c [in part].—Spurgeon, 1915: 385, 386 [in part].—Pratt, 1916:391, 392, fig. 625 [in part].—Ortmann, 1918:838, 848 [in part].—Garman, 1924:88, 89.—Spandl, 1926:95, 141–142, 148 [in part].—Stiles and Hassell, 1927:219 [in part].—Chappuis, 1927:91, 120 [in part].—Creaser, 1931:10; 1932:336.—Giovannoli, 1933a:618–619, fig. 90; 1933b:236–237, fig. 90.—Wolf, 1934–38:104 [in part].—Turner, 1935:876.—Park, 1938:209.—Fleming, 1939: 304, 305.—Bouvier, 1940:68 [in part].—Park et al., 1941:154–171, 5 figs.—Rhoades, 1941:141, 142, 144.—Hobbs, 1942a: 335, 338, 342, 351, 352 [in part].—Jeannel and Henrot, 1949:21.—Bott, 1950:25.—Dearolf, 1953:229.—Hobbs and Barr, 1960: 19.—Vandel, 1964:448, 453, 461, 501, 502, fig. 76.—Hobbs, 1967a:125.
Crabs.—Darwin, 1859:137.
Eyeless Crabs.—Binkerd, 1869:86.
Cambarus pelulcidus.—Hagen, 1870: 106 [Erroneous spelling].
Orconectes pellucidus.—Cope, 1872a:409, 410, 419; 1872b: 161, 162, 173, 174; 1879:492, 494, 495, 505, 506 [in part].—Cope and Packard, 1881:879, 881, 882.—Joseph, 1882:12.—Wright, 1884:272, 273.—Faxon, 1884:139.—Underwood, 1886:371.—Packard, 1888:24, 126, 140, 155, pl. 21, fig. 2, pl. 22, fig. 7.—Packard, 1894:735, 742.—Hobbs, 1948a:19.—Pennak, 1953:458 [in part].—Eberly, 1954:59; 1958:1, 2, 3 [in part].—Wells, 1959:5–7.—Eberly, 1960:29, 30, 31 [in part].—Brown, 1961: 929, 930.—Creaser, 1962:3 [in part].—Rhoades, 1962: 68, 79, 94.—Fitzpatrick, 1963:60.—Holthuis, 1964:42, 43, 45, 47.—Vandel, 1964:509, 570, 575 [in part].—Mohr, 1964:828.—Poulson, 1964:752, 756, 757, 759, 762, 764.—Frey, 1965:623, 624.—Fitzpatrick, 1967:141, 142.—Mohr and Poulson, 1966:166, 204.—Barr, 1967a: 160, 161, 186, 187, 192, pl. 46, fig. 10; 1967b:480.—Hobbs, 1967a:130; 1967b:12 [in part].—Thompson, 1967:46, 47.—Barr, 1968:65, 91, fig. 18; 1971:71, 72.
Astacidae.—Shaler, 1875:361; 1876:10.
Cray fish.—Shaler, 1875:362, 363; 1876:11, 12.
Cambarus typhlobius Joseph, 1880:202.—Faxon, 1884:139; 1885a:7, 45.—Underwood, 1886:373.—Hay, 1896:477.—Harris, 1903b:131, 151.—Faxon, 1914:427.—Bouvier, 1940:68.—Van Straelen, 1942:2.—Bott, 1950:25.—Villalobos, 1953:348.—Villalobos, 1955:11.—Holthuis, 1964: 42, 43, 44, 45, 46, 47.
Cambarus stygius Joseph, 1881:241, 249 [nomen nudum]; 1882: 12 [homonym].—Underwood, 1886: 373.—Packard, 1888:86, 123.—Faxon, 1914:427.—Spandl, 1926:95.—Stammer, 1932:608.—Wolf, 1934–1938: 105.—Holthuis, 1964:42, 43, 44, 45, 47. [Not Cambarus stygius Bundy, 1876.]
Cambarus coecus Joseph 1881:237 [nomen nudum].—Faxon, 1884:139; 1885a:7, 45; 1914:427.—Holthuis, 1964:42, 45.
Blind crayfish.—Semper, 1881:77.—Call, 1901:101.
Cambarus (Orconectes) pellucidus.—Hovey, 1882:222 [in part].
Orconectes.—Hovey, 1882:223 [in part].—Barr, 1968:85; 1971:72, 85, 86.
Cambarus Stygius.—Faxon, 1884:139; 1885a:7, 45, 46.—Bott, 1950:25.
Camtarus (Orconectes) pellucidus, form inermis.—Packard, 1888:156, pl. 27, fig. 5. [Erroneous spelling of Cambarus.]
Astacus Cambarus Stigius.—Rabé, 1890:9.
Cambarus.—Apfelbeck, 1895:24.—Bolivar et Jeannel, 1931: 306, 307, 309.—Vandel, 1964:494, 495, 512.
Cambrus pellucidus.—Price, 1900: 155 [erroneous spelling].
Crayfish.—Call, 1901:100.
Cambarus (Faxonius) pellucidus.—Ortmann, 1905a:107, 108, 111, 114, [in part]; 1905b:435 [by implication]; 1931:64, 65 [in part].—Fage, 1931:373 [in part].—Turner, 1935:876.
Cambarus caecus.—Bouvier, 1940:68 [erroneous spelling of coecus].
Cambarus pellucidus pellucidus.—Rhoades, 1941:144. Cambarus pelludicus.—Dearolf, 1942:50 [Erroneous spelling].
Crawfish.—Dearolf, 1942:52.
Cambarus Pellucidus.—Jackson, 1942:4.
Cambarus (Cambarus) pellucidus.—Balss, 1944:402; 1955: 1311, 1312.
Orconectes pellucidus pellucidus.—Rhoades, 1944:112, 113, 115, 117, 120, 121.—Hobbs, 1948a:16, 19, 20.—Rhoades, 1959:401.—Cole, 1959:81.—Eberly, 1960: 30.—Hobbs and Barr, 1960: 19.—Nicholas, 1960: 133.—Barr, 1961:32.—Rhoades, 1962:68, 90, 91.—Wolfe and Cornwell, 1964: 1467, 1468.—Jegla et al., 1965: 639.—Hart and Hart, 1966:8, 9.—Jegla, 1966:346, 347, 353.—Hobbs, 1967a: 131; 1967b: 7.—Barr, 1968:60.
Orconectes pellucidus pelluicdus.—Hobbs, 1948a: 16 [erroneous spelling].
Cambarus Coecus.—Bott, 1950:25.
Gambarus typhlobius.—Croizat, 1958:908 [Erroneous spelling].
Orconectes (Orconectes) pellucidus.—Hobbs, 1959:890 [in part].
Crayfishes.—Barr, 1964:79; 1966:15.
REVIEW OF LITERATURE.—The first reference to this crayfish that has come to our attention is an anonymous account of the occurrence of a white crayfish in Mammoth Cave published in “Das Ausland” on 13 January 1843. In the same year, an anonymous record of a gift of “a white eyeless crayfish (Astacus Bartoni ?)” from Mammoth Cave, Kentucky, by W. T. Craige to the Academy of Natural Sciences appeared. In 1844, Thompson reported a blind “crayfish” from Mammoth Cave and considered it to be conspecific with A. bartonii. Tellkampf (1844a), however, disagreed with Thompson as to the identity of the crayfish occurring in Mammoth Cave and referred to it in a footnote in “Das Ausland,” on 19 June as follows: “Astacus pellucidus, unserem A. fiuviatilis verwandt, dessen Grosse er jedoch nicht erreicht. Die Scheren des ersten Fusspaares, sind schlank und zart, des vorderste Glied wenig gebogen, schwach gezähnt. Die Augen liegen unter dem Kopfschilde versteckt.” In the text referring to this footnote he stated that “Nur wenige Schritte waren wir gegangen, als ich einen kleinen, ungefähr 1¾ Zoll longen Krebs*) in dem seichten Wasser erblickte, den ich ohne Mühe fing. Er war weiss und seine Schale so durchsichtig, das man die Bewegung der Kiemen und die innern Thiele durchscheinen sah.” Whereas in the same year (Tellkampf 1844b), a more complete description appeared that has consistently been cited as the original description, it bears no specific date of publication. Therefore, it seems to us that the description quoted above must take precedence. The more complete description is as follows:
“Der Astacus pellucidus Nob. ist unserem A. fluviatilis verwandt, erricht aber nicht dieselbe Grosse. Die Scheeren des ersten Fusspaares sind schlank und zart, des vorderste Glied wenig gebogen, schwach gezähnt. Die Augen stehen nicht vor, sondern sind unter dem Kopfschilde verstechkt. Die Fühler lang und sehr grazil. Die ersten Glieder der zwei vorleitzien Fusspaare haben auf ihrem vorderen Rande ein nach vorn und inner gerichtetes, etwas gebogenes Horn, das Horn des letzten Fusspaares ist nur angedeutet. Thomson sagt, dass der Krebs mit Astacus Bartoni ubereinstimme, allein er ist davon bestimmt verschieden.” The following year, an English translation of Tellkampf’s paper appeared.
Erichson (1846) redescribed the species, adding several additional characters, and assigned it to his new subgenus Cambarus. Gibbes (1850) and Silliman (1851) referred to specimens from and in Mammoth Cave.
Girard (1852) elevated the subgenus Cambarus to generic rank and was the first person to mention the “anterior pair of abdominal legs” of male crayfishes, indicating that the tips are “twisted in C. pellucidus.” In the same year, Dana discussed the relationships of the American crayfishes to those occurring elsewhere and to the lobsters and other Reptantia.
In 1855, Newport recorded the first detailed observations on the eyes of this crayfish, and Lucas (1864) indicated that organs of vision were lacking. Darwin (1859) referred to the eyes of blind crabs in Carniole and Kentucky but added no original data. Binkerd (1869) referred to pellucidus as an eyeless crab which was rather scarce and seems to be “destitute of the power of hearing, but any motion imparted to the water seemed to create alarm. They probably have a high nervous sensibility, which is not inconsistent with their fair, soft, gelatinous appearance, in which they do not differ from the fish.” He further supposed that they were viviparous.
Hagen (1870), in his monograph of the American Astacidae, presented a description of the species in Latin together with illustrations. He discussed its affinities with his Group I [= Procambarus] and Group II [=Orconectes], and pointed out that it is the most aberrant species of the genus.
Cope (1872a and 1872b, essentially identical articles) compared the fauna of Wyandotte and Mammoth caves and erected the genus Orconectes to receive the albinistic crayfishes occurring in them, defending the rationale of proposing a new genus to receive the two troglobites. Packard (1871 and 1872b) are essentially identical. In discussing the inhabitants of Mammoth Cave and their evolution, he emphasized Hagen’s observations on the atrophied eyes and presented a dorsal view of the animal which was redrawn from Hagen’s figure.
Hagen (1872) not only pointed out the folly of Cope’s erecting the genus Orconectes but also added that Cope had not given “any character by which to separate it [O. inermis] from the old species, C. pellucidus.”
Putnam (1872) simply quoted a sentence from the anonymous article (1843). Packard (1873) and Smith (1873 and 1875) agreed with Hagen that Cope’s O. inermis was not specifically different from C. pellucidus and that the species should be retained in the genus Cambarus.
Packard (1874), at an entomological meeting of the Boston Society of Natural History, exhibited drawings of the supraoesophageal ganglia of this crayfish and of an epigean species; the differences noted were mainly in the enlargement of the “sides of the ganglion in the blind species.” He showed further that the pigment cells are white and stated that the whole eye was “in a state of arrested development.”
Putnam (1875a) demonstrated several living pellucidus from Mammoth Cave at the 2 December 1874 meeting of the Boston Society of Natural History, and (1875b) the same specimens had been exhibited at the Essex Institute on 25 November, 1874. He added another locality for the species—a cave several miles down the Green River from Mammoth Cave and on the opposite bank (perhaps Ganter’s Cave).
Shaler (1875) referred to the Astacidae in Mammoth Cave and speculated on its origin with reference to Pleistocene glaciation. He expressed the view that the cave fauna had been derived from, and was being reinforced by interbreeding with, the epigean fauna.
Putnam (1877) recounted observations of feeding behavior, molting, and regeneration of appendages among specimens retained in the laboratory from 13 November 1874 until 7 August 1875. One female molted twice, 28–29 January and again on 20 April with almost complete regeneration of legs and antennae following the second molt. During this time the animals withstood temperatures varying from a heated room to those which froze “the water in their jars.”
Cope’s (1879) reference to the crayfish is only a slightly modified version of his 1872 contribution. Packard (1879) discussed and figured the eyes and brain of this crayfish, comparing them with those of an epigean crayfish from Iowa. The figure of the entire crayfish is the same as that published in 1871.
Hubbard (1880) simply recorded having collected “good specimens” of pellucidus in Mammoth Cave. Joseph (1880), in a brief note, proposed the name C. typhlobius for a cave crayfish ostensibly inhabiting a cave in Yugoslavia. The following year (1881) he referred to the species as both C. coecus and C. stygius, and in a third paper (1882) compared the specimen, to which he referred as C. stygius, with Packard’s description of Cambarus pellucidus. Hovey (1882) utilized a new combination, Cambarus (Orconectes) pellucidus, but contributed no original information.
Cope and Packard (1881), in discussing Cope’s O. hamulatus, indicated that it and O. pellucidus probably arose from different species of Cambarus and Cope contrasted the two species. Semper (1881) added no additional information, simply stating that the blind crayfish of Mammoth Cave was well known!
Leydig (1883) presented a histological study of the eyes and antennae of specimens of pellucidus from Mammoth Cave, extending the earlier observations of Newport and Packard.
Faxon (1884) considered Cope’s O. inermis to be conspecific with Cambarus pellucidus. He cited Joseph’s work and indicated that “until a more satisfactory account of this discovery is published, one may well hesitate to admit the Carniola Cambarus [typhlobius] into the list.”
Wright (1884) reviewed Leydig’s findings and compared the “olfactory cones” of O. pellucidus with those of C. propinquus [=O. propinquus], reporting many more in the former.
Faxon (1885a) presented an excellent summary of, and commented on, the contributions of previous authors concerning this species. He discussed its affinities, and, in so doing, assigned it to his Group I (=Procambarus, in part). He considered Cope’s O. inermis a synonym of Cambarus pellucidus from the Mammoth Cave region and, erroneously, from Wyandotte Cave and a cave in Bradford, Harrison County, Indiana. He also recorded Joseph’s work and quoted his description of C. stygius in full, lamenting the fact that a fuller description had not followed. In a later paper (1885b), Faxon cited a new locality for O. pellucidus, White Cave, Kentucky.
Underwood (1886), in his list of North American freshwater crustaceans, presented a partial synonomy of C. pellucidus and recorded it from Kentucky and Indiana, following Faxon in considering Joseph’s C. typhlobius and C. stygius doubtful species.
Packard (1888) constitutes the broadest treatment in existence of the then known troglobitic crayfishes. He quoted extensively from and summarized the contributions of previous investigators, treating taxonomy, distribution, food and feeding habits, auditory, optic, and olfactory senses, ecology, and evolution. While he considered O. inermis to be a synonym of C. pellucidus, he relegated Cope’s genus to subgeneric rank and indicated that the two cave species, pellucidus and hamulatus, constituted its members (page 42). In considering the origin of C. pellucidus, he stated (page 39) that “it either is derived, with C. affinis [=O. limosus Rafinesque], from a common ancestor; or … what seems more probable, it is a modification of C. affinis or an allied species, e.g., rusticus. The characteristics which separate C. pellucidus from C. affinis or C. bartonii or any out-of-door species are those which have been induced by its life in total darkness and the diminution of its food-supply.” Perhaps through a printer’s error, he utilized the combination, “Camtarus (Orconectes) pellucidus, form inermis” to designate plate-figure 27:5, which is identical to the figure to which he referred earlier (1871) as Cambarus pellucidus, one that had been redrawn from Hagen, 1870.
Garman (1889) was impressed by the fact that C. pellucidus is more closely allied to the Missouri C. virilis than is C. setosus which, in turn, is more similar to the Kentucky C. bartonii than is C. pellucidus, and he suggested the derivation of C. setosus from C. bartonii, concluding (page 236) that, “Such close affinities as exist between C. bartonii and C. setosus do not permit their separation into different genera, and the retention of the latter in the genus Cambarus cannot but be followed by the disestablishment of the genus Orconectes and the return to the older genus of the two species heretofore included in the latter.”
Faxon (1890) compared the arrangement of the olfactory setae of this species with that of C. setosus; he further postulated that “The closer superficial likeness between C. pellucidus and C. hamulatus, belonging to different sections of the genus, than between C. hamulatus and C. setosus belonging to the same section, may be explained by the longer period of time during which the subterranean influences have probably been exerted upon the first two species.” In the same year, Rabé indicated that Astacus Cambarus pellucidus occured in Mammoth Cave and Astacus Cambarus Stigius [sic] had been found in the caves of Carniole.
Packard (1890) in his discussion of the effect of cave life on animals and its bearing on the evolutionary theory referred to the eyes of pellucidus. Parker (1890) compared the eyes of pellucidus with those of C. setosus and found those of the former to be without pigment, shaped like a blunt cone, lacking facets but possessing an optic ganglion and nerve, of which the terminus of the latter was “not discoverable.” At the apex of the cone he found a “lenticular thickening of the hypodermis, in which there exist multinuclear granulated bodies.”
Hovey (1891) stated that pellucidus feeds on “Crangonyx and other minute crustacea.” Nothing of significance was added by Ortman (1892), Cunningham (1893), or Stebbing (1893). Packard (1894) noted that the “eyes of the young are perceptibly larger in proportion to the rest of the body than in the adult,” and quoted Tellkampf (1844), “the eyes are rudimentary in the adults, but are larger in the young.” Packard also stated that “the blind crayfish of Mammoth Cave … have, as we have ascertained by anatomical investigation, degenerate ears, so that the sense of hearing is with little doubt, nearly, if not quite obsolete.”
Lönnberg (1894 and 1895) contrasted Procambarus acherontis with pellucidus and suggested that the latter is probably an older species. In the same year Packard referred to pellucidus but contributed no additional information relative to it.
Apfelbeck (1895) stated that specimens of an eyeless Cambarus from the subterranean waters of Herzegovina were in the Musée de Vienne.
Hay (1896) contrasted his C. pellucidus testii with the nominate subspecies and reiterated the fact that C. typhlobius was the only member of the genus which occurs beyond the limits of the North American continent.
Call (1897) cited specific areas in Mammoth Cave where pellucidus occurs. Hay, in the same year, presented a synonomy for C. pellucidus, including inermis as a synonym.
Faxon (1898) referred to Hay’s (1893) Indiana records for pellucidus [= inermis] and indicated that the specimens from them, while transitional between pellucidus and testii, are more like O. inermis (Wyandotte Cave) than like the typical form around Mammoth Cave, pointing out the reduction of spines in northern specimens.
Eigenmann (1899) on 23 November 1898 collected in Mammoth Cave a single female carrying young, the only record, to our knowledge, of a female with young. In the same year, Hay included pellucidus in his key to the crayfishes, and, in citing its range, obviously considered inermis a junior synonym.
Price (1900) is simply a title without text (see bibliography). Call (1901) contributed no new data relating to this crayfish. Ortmann (1902) believed pellucidus to be related to species presently assigned to the genus Procambarus and treated inermis as a synonym of pellucidus.
Hay (1902a), in relating observations on pellucidus in Mammoth Cave stated that “when first observed they were usually on the bottom, resting quietly with their legs and antennae fully extended. Unless they were disturbed they would remain in this position for several minutes, and then with no apparent reason start off at a rapid gait, move to another spot and take up the same position,” gently moving the antennae to and fro. When disturbed, they move “slightly about in various directions” before swimming away, but “there seemed to be no ability on the part of the animal to select a safe haven of refuge from a distance.” When cornered, they would rise high on their forelegs, waving their chelae in the direction of danger. In drying pools, they burrowed or crawled under a stone where, he concluded, they were vulnerable to the cave rat. Disturbances at the surface of the water seemed not to frighten the animals, and he believed that “senses of sight and hearing have entirely disappeared.” On the basis of his observations he concluded that copulation occurs in the early fall and stated that the females “are said” to lay their eggs during the winter. In a later paper (1902b), Hay contrasted pellucidus and C. hamulatus and stated that “… C. pellucidus and C. acherontis [probably Procambarus l. lucifugus (Hobbs)], which are very dissimilar in general appearance, are closely related.”
Steele (1902), Eigenmann (1903), and Harris (1903a) contributed no additional information about this crayfish, but Harris (1903b) summarized the conclusions and observations of others.
Ortmann (1905a, 1905b) expressed the opinion that pellucidus was more closely related to the members of the “fourth group” than to those of the “first,” and assigned it to his subgenus Faxonius [=Orconectes], defending this opinion on morphological and zoogeographic grounds, and placed it in the most primitive section of the subgenus, the Limosus Section. Bell (1906) simply reviewed the observations made by others on the sense organs.
The references to pellucidus by Banta (1907), Graeter (1909), and Pearse (1910) include summaries or observations made by others cited above. Osborn (1912) added no original data. Hovey’s (1912) contribution consists of photographs of a male and female pellucidus together with the statement that the species “feeds on aquatic crustacea which it deftly extracts with its pincerlike claws from under flat stones.”
Faxon’s (1914) checklist included O. inermis as a synonym of C. pellucidus, and in it C. stygius, C. coecus, and C. typhlobius are cited as “doubtful species.”
The account of the eye by Spurgeon (1915) is based on observations of O. i. inermis, and he made no additional contribution to our knowledge of O. pellucidus. Pratt (1916) and Ortmann (1918) included pellucidus in their keys but contributed no new data. Ortmann (1931) stated that C. sloani and C. indianensis [both now assigned to the genus Orconectes] are the species most closely allied to pellucidus and “probably are the last remnants of the surface-stock from which C. pellucidus descended.”
The following based their statements about pellucidus on data cited above or on other that are essentially identical: Garman (1924), Spandl (1926), Stiles and Hassall (1927), Chappuis (1927), Creaser (1931, 1932), Bolívar and Jeannel (1931), and Fage (1931).
Stammer (1932) expressed the opinion that Joseph’s C. stygius was identical with Astacus fluviatilis [= Astacus astacus Linnaeus].
The observations of Giovannoli (1933a, 1933b) on pellucidus in Mammoth Cave are essentially identical to those of Hay and others. “Usually it is observed at rest but occasionally it is seen walking along as if it knew where it was going. They seem to lack entirely the inclination so characteristic of above-ground species to retreat under rocks and planks. They pay no attention to such shelters either when undisturbed or when frightened. When merely suspicious of danger they walk slowly towards deeper water, but if startled they swim blindly backward just as any crayfish does.” Wolf (1934–1938) contains no new information about pellucidus.
Turner (1935), in recording aberrant secondary sexual characteristics in crayfishes, reached the same conclusion as did Ortmann that the presence of hooks on the ischia of the fourth pair of pereiopods in the male represents a derived, rather than primitive, condition. Park (1938), concerned with periodicity of activity in various animals, found pellucidus to be arhythmic. Fleming (1939) and Bouvier (1940) made no original contributions, and Rhoades (1941) simply compared pellucidus pellucidus with his C. p. australis.
Park et al. (1941) reported pellucidus to be photonegative and presented data to indicate an arhythmic activity pattern. Neither Dearolf (1942) nor Van Straelen (1942) added to our knowledge of the species. Jackson (1942) gave a brief account of the habits of this crayfish and reported having kept an adult alive in an aquarium for a month.
Hobbs (1942a) assigned pellucidus to the resurrected genus Orconectes, pointing out that Faxonius of previous authors is a synonym of Orconectes. Balss (1944 and 1955) contributed no additional information to our knowledge of pellucidus and was unique in utilizing the combination Cambarus (Cambarus) pellucidus.
Rhoades (1944) presented a description of his new subspecies, O. pellucidus packardi, comparing it with the nominate subspecies and O. p. australis. He summarized their ranges and assigned the three subspecies of pellucidus and three additional epigean species to his “Group rafinesquei.” Hobbs (1948a) figured the first pleopods of the males of O. pellucidus and related species, questioned Rhoades’ division of the Limosus Section, and expressed the opinion that inermis represented a species distinct from pellucidus. Jeannel and Henrot (1949) reported a new locality for the species, Cave City Cave, Barren County, Kentucky.
Bott (1950), concerned with Joseph’s species reported from Carniole, did not reach a conclusion as to its identity. Pennak (1953) added no original information about pellucidus, and his figure 286 is an illustration of O. inermis testii. Villalobos (1953, 1955) considered the existence of Joseph’s C. typhlobius as perhaps a relict of the crayfishes “que en otra épocas poblaron el suelo europeo.”
Dearolf (1953) cited dates of observations of this crayfish in three Kentucky caves.
Eberly (1954) stated that the cave crayfishes (including O. pellucidus) “occupy the highest niche in the biosystem of the cave.” In 1958 and 1960, he summarized what he considered to be the adaptations of the crayfishes to a cave environment, agreed with his predecessors on their antiquity, and gave a broad generalization regarding their origin. Croizat (1958) added nothing directly to our knowledge of O. pellucidus; however, he consistently used Gambarus instead of Cambarus for the American genus.
Rhoades’ (1959) contribution included a history of the nomenclatural changes among the troglobitic Orconectes and an interpretation of the relationships of pellucidus, inermis, and testii, concluding that the latter is a synonym of inermis and that inermis freely intergrades with pellucidus in southern Indiana, thus recognizing O. pellucidus pellucidus and O. p. inermis.
Cole (1959) and Wells (1959) presented no original information about pellucidus nor did Hobbs and Barr (1960), Nicholas (1960), or Barr (1961). Hobbs (1959) included O. (O.) pellucidus in his key to the crayfishes of the United States, indicating that four subspecies occurred from Alabama to Indiana.
Brown (1961) reported that a re-examination of the data of Park et al. (1941) had “indicated a statistically significant … 24-hr. rhythm of activity to be present … with minimum activity about 9 a.m. and maximum about 7:00 p.m.” He further stated that members of pellucidus “have no eyes.” Creaser (1962) discussed the affinities of O. pellucidus, maintaining that only pellucidus and lancifer should be assigned to the genus Orconectes. Rhoades (1962) presented a diagnosis of O. p. pellucidus and stated that it is “widely distributed in the solution caverns between the Cumberland River and the counties of southern Indiana” where they “are generally seen in the edges of a clear stygian pools or hiding under rocks.” He further postulated the origin of the species from a stock which had “its origin in the Ozarkian Highlands in the late Miocene.”
Fitzpatrick (1963), in presenting a background for elevating the subgenus Faxonella to generic rank, reviewed Creaser’s (1962) remarks about O. pellucidus. Barr (1964) contributed no new data or hypotheses concerning the species. Holthuis (1964) reviewed the history of Joseph’s three crayfish names and presented a convincing conclusion that C. typhlobius is a synonym of A. pellucidus Tellkampf, and that Joseph’s specimens were simply mislabeled members of Tellkampf’s species. C. coecus Joseph was declared a nomen nudum, and C. stygius Joseph a synonym of C. typhlobius, becoming thereby a synonym of A. pellucidus. Vandel (1964) presented an excellent account of the various contributions of others to our knowledge of the biology of the species. In the same year, Wolfe and Cornwell reported that although small amounts of B-carotene and lutein were present in O. p. pellucidus, “astaxanthin, the principal carotenoid of most Crustacea” is absent, supporting their conclusion that “pigmentation is dependent on the amount of carotenoid in the diet rather than on the presence of light.” It is also suggested that this crayfish lacks, and perhaps never had, “the ability to oxidize dietary carotenoids.”
Mohr (1964) presented a photograph of O. pellucidus and made the statement that it “may live to twice the age of surface kin.” Poulson (1964) recounted the observations of Barr (personal communication) that breeding (ovulation?) in O. pellucidus “precedes low water by one to two months, and high water, with maximum organic inwash, by four to six months. Further, he stated that “the restriction of … young crayfish to springs and backwaters must be related to current, small food-particle size, clay, or other factors because these habitats and adult habitats shows no differences in CO2 or carbonate alkalinity.” Discussing light, Poulson stated: “Light stimulation of the brain area, reduced eye stalk, or 6th abdominal ganglion results in negative reaction to light,” and he reported that a “kinetic component is found … [in] O. pellucidus … since they turn away when illuminated on one side.”
Frey’s (1965) remarks relative to O. pellucidus were largely condensed from Rhoades’ (1944, 1959) conclusions and postulates. Jegla et al. (1965) compared the maximum lengths of individuals in populations of troglobitic Orconectes (O. i. inermis, O. pellucidus, and O. australis) and found a difference between them of 20 mm, the same difference in length at which they reached sexual maturity, as well as one “in inflection point for cheliped allometric growth. These variations may be a result of different levels of food supply and interspecific competition. They do not appear to be influenced by two-fold variation in population size, eight-fold variation in population density, or ten-fold variation in available habitat.” Predation by fishes was postulated to reduce population density but seemed to have no effect on maximum length attained at sexual maturity. Length was believed to be associated with available food and perhaps influenced by inter-specific competition.
Hart and Hart (1966) reported that O. pellucidus is infested with the following entocytherid ostracods: Dactylocythere ungulata (Hart and Hobbs, 1961), Sagittocythere barri (Hart and Hobbs), and S. stygia Hart and Hart. Jegla (1966) reviewed previous references to molting and reproduction in this species.
Barr (1966) referred to Tellkampf’s description of this species.
Mohr and Poulson (1966) presented a drawing of O. pellucidus, and stated that “Scientists now believe … that the ancestors of our commonest cave crayfish, Orconectes pellucidus, were isolated in caves at the beginning of the Pleistocene epoch.”
Barr (1967a, 1967b) noted the northern boundary of the range of O. pellucidus, indicating its occurrence in “the south Pennyroyal fauna,” and included a photograph of a living first-form male. Neither Fitzpatrick (1967) nor Hobbs (1967a) added to our knowledge of the species, and Hobbs (1967b) only proposed that “at least some of the similarities” between Procambarus pecki and O. pellucidus “are due to convergence.”
Thompson (1967) observed that O. pellucidus, in contrast to epigean crayfish maintained in an aquarium, “rather than folding its antennae back in a streamlined position as the epigeal form did while walking through vegetation, the cave form held them forward for tactile cues, and consequently often became tangled in the litter. It also lacked cryptic responses when startled and spent little time hidden under rocks, compared to the epigeal form.” Thompson did not cite the source of his O. pellucidus, and it is possible that his animal was a member of one of the subspecies of O. inermis.
Jegla and Poulson (1968), reviewing the work of Park et al. (1941) and that of Brown (1961), concluded that the data of Park et al. cannot “be used to distinguish between endogenously and exogenously controlled rhythms.” They found “evidence of a circadian clock mechanism” with “average periods of 26, 27, and 34 hours” in O. pellucidus [=O. inermis inermis and O. inermis x testii].
Barr (1968) expressed the opinion that the steepening of stream gradients in the Pennyroyal and Cumberland plateaus from Alabama to Indiana at the close of the Pliocene or early Pleistocene was primarily responsible for the extinction of the ancestors of the troglobitic Orconectes, and that the quieter streams of caves served as refuges for the evolving troglobites. He also presented a graph redrawn from the 24-hour activity data of Park et al. (1941), and criticized Brown (1961) for not utilizing all of Park’s published data.
Barr and Kuehne (1971) discussed the role of this crayfish in the Mammoth Cave ecosystem.
DIAGNOSIS.—Albinistic; eyes reduced and without pigment; rostrum with marginal spines or tubercles delimiting base of acumen, margins subparallel, convex or converging, upper surface concave and without median carina; postorbital ridges usually terminating cephalically in spines or tubercles; hepatic area with or without two to many spines; at least one, often several cervical spines or acute tubercles present; areola 3.7 to 6.0 times longer than broad and constituting 34.1 to 42.2 percent of entire length of carapace; chelae not conspicuously setose but with ciliated tubercles, mesiodorsal surface of palm with several irregular rows of tubercles; hooks on ischiopodites of third and fourth pereiopods. First pleopod of first-form male with greatest cephalocaudal diameter of pleopod more than twice that immediately proximal to base of central projection, always terminating in only two elements; non-corneous mesial process broad basally, triangular, directed distally and slightly caudally and extending considerably beyond distal extremity of central projection, frequently almost obscuring latter in caudal aspect (Figure 14j); central projection small, corneous, flattened in cephalocaudal plane, and directed distad; slight swelling at cephalic base of central projection. Annulus ventralis only slightly broader than long, highest along median portion, and without shelf-like rim along caudal margin (Figure 14l).
Topotypic Male, Form I: Body (Figure 14c, h) subovate, depressed. Abdomen narrower than thorax (11.0 and 12.6 mm in widest parts, respectively). Width of carapace greater than depth in region of caudodorsal margin of cervical groove (12.5 and 10.2 mm). Areola moderately broad (4.5 times longer than wide), with about 6 widely spaced, minute punctations across narrowest part. Cephalic section of carapace 1.6 times as long as areola; length of areola 38.6 percent of entire length of carapace. Rostrum approximately twice as broad as long, excavate, and with length of acumen subequal to width of rostrum at base; cephalic extremity reaching far beyond antennular peduncle and slightly beyond antennal peduncle; margins not swollen, only slightly elevated, and with prominent corneous-tipped marginal spines at base of acumen; upper surface with evenly spaced minute setiferous punctations; subrostral ridges very weak and evident in dorsal aspect along basal fourth of rostrum.
Postorbital ridges relatively weak, short, with shallow dorsolateral grooves, and terminating cephalically in prominent corneous-tipped spines. Suborbital angle lacking. Branchiostegal spines acute. Six and eight cervical spines present on right and left sides of carapace, respectively. Carapace punctate dorsally and granulate laterally; hepatic area with about 12 spines of various sizes together with several tubercles. Abdomen slightly longer than carapace (32.0 and 30.0 mm). Cephalic section of telson with 2 strong spines in each caudolateral corner, mesial ones movable.
Epistome (Figure 14g) subtriangular, with almost straight cephalolateral margins and rounded basal lateral extremities; ventral surface subplane with crowded minute setiferous punctations. Eyes much reduced, completely hidden under rostrum in dorsal aspect and extending only halfway between margin of orbit and marginal spines of rostrum. Antennules of usual form with prominent spine near distoventral extremity of basal segment. Antennae extending caudally at least to caudal margin of telson. Antennal scale (Figure 14i) broadest distal to midlength, about 2.2 times longer than broad; outer thickened portion much narrower than lamellar area and terminating in prominent corneous-tipped spine. Third maxilliped extending almost to end of basal third of ultimate podomere of peduncle of antenna.
Chela (Figure 14f) slender and little inflated; mesial margin of palm 1.3 times longer than width of palm; palmar area tuberculate, with fine plumose setae at distal bases of tubercles; ventral surface with prominent corneous-tipped tubercle opposite base of articulation of dactyl; tubercles along mesial surface arranged in sublinear series with 12 tubercles in mesialmost row; distal two-thirds of lateral margin of palm and proximal fourth of fixed finger weakly costate. Fingers not gaping; dorsal and ventral surfaces of both with median longitudinal ridges flanked by setiferous punctations; opposable margin of immovable finger with row of 14 rounded corneous tubercles, fourth from base largest; same margin with large tubercles below row and between eighth and ninth tubercle; row of minute denticles broken by 8 basal tubercles and continuous distally to base of corneous tip of finger; opposable margin of dactyl with row of 18 tubercles, fourth and fifth from base subequal in size and larger than others in row, row of minute denticles extending almost entire length of finger and interrupted by tubercles; mesial surface of dactyl with tubercles along proximal half and punctations along distal. Carpus longer than broad and tuberculate; mesial surface of right with 1 (left with 2) large spine and more proximal moderately large acute tubercle; distoventral margin with 2 prominent spines, 1 adjacent to ventrolateral articulation with propodus, 1 situated more mesially. Merus tuberculate except proximolaterally, upper surface with 4 or 5 corneous-tipped spines near distal end, and ventral surface with lateral row of 14 spikelike tubercles and mesial one of 13, few additional tubercles flanking latter two rows. Ischium with row of 6 small tubercles on opposable margin, other smaller ones lateral to row and on outer surface.
Ischia of third and fourth pereiopods (Figure 14k) with simple hooks, those on third conspicuously larger than those on fourth but neither extending proximad of distal extremity of corresponding basis. Coxae of fourth pereiopods with heavy, caudomesially projecting prominences; coxae of fifth without prominences except for small mesioventral projection on ventral border of rim surrounding basal portion of phallic papillae.
First pleopods (Figure 14a, e, j, k) symmetrical, reaching coxae of third pereiopods wiren abdomen is flexed and situated in shallow, broad sternal arch; tip ending in two parts as described in Diagnosis.
Basal podomere of uropods with 2 prominent spines, each overhanging lateral portions of corresponding ramus and small but conspicuous “telsonic condyle” projecting dorsomesially from its mesiodistal angle. Inner ramus of telson without well-defined longitudinal median carina and spine but with spine on distolateral angle; outer ramus with row of spines on distal margin of proximal section, lateral 1 or 2 longer than others.
Topotypic Female: Differing from holotype in following respects: Acumen not quite reaching distal end of antennal peduncle; 5 and 6 cervical spines on left and right sides of carapace, respectively; hepatic area with only 7 well-defined spines; projecting portion of epistome shorter with cephalolateral margins slightly convex; third maxillipeds not quite reaching distal podomere of antennal peduncle; opposable margin of immovable finger of cheliped with row of 15 tubercles, fifth from base largest, that of dactyl with 18, sixth from base largest; upper surface of merus with 5 and 2 spines on left and right chelipeds, respectively, and ventrolateral margin with 11 and ventromesial margin with 17 and 12 on right and left; ischium with 7 irregularly arranged acute tubercles. First pleopods uniramous and reaching midlength of annulus when abdomen is flexed.
Annulus ventralis (Figure 14l) shallowly situated in sternum and not firmly fused to sternal plate immediately cephalic to it; outline subovate, only slightly broader than long, with median portion elevated ventrally and forming broad arc having its highest segment distinctly caudal to midlength; arched portion bearing only faint longitudinal grcove, ending caudally on vertical wall, plateau-like rim totally lacking; sinus very short, originating dextral to caudal end of longitudinal groove, following gentle arc across median line, passing dorsally and ending on caudal wall sinistral to median line.
Topotypic Male, Form II: Differing from holotype in following respects: areola with only 4 punctations across narrowest part; only 4 cervical spines and only 5 hepatic spines on each side of carapace; opposable margin of immovable finger of cheliped with row of 10 tubercles, corresponding margin of dactyl with 12; merus of cheliped with 3 spines on upper distal surface, 8 in ventrolateral row and 13 in ventromesial row; ischium with row of 5 tubercles.
Hooks on ischia of both third and fourth pereiopods much reduced, those on fourth to low tubercles; protuberances on coxae of fourth pereiopods only slightly reduced in size.
First pleopods (Figure 14b, d) markedly similar to those of holotype; however, central projection rounded, poorly defined, and non-corneous.
SIZE.—The largest specimen available to us is a first-form male from Crystal Lake in Mammoth Cave, Edmonson County, Kentucky, which has a carapace length of 39.4 mm. The smallest first-form male, carapace length 22.0 mm, was collected in Cooks Cave, Logan County, Kentucky.
MEASUREMENTS (in millimeters).—Orconectes pellucidus:
TYPES.—Holotype, Zoologisches Museum der Humboldt-Universität, Berlin (♂ I).
TYPE-LOCALITY.—Mammoth Cave, Edmonson County, Kentucky.
SPECIMENS EXAMINED.—Specimens from Kentucky and Tennessee were examined as follows:
KENTUCKY: Barren County: (1) Cave City (=Railroad) Cave, in town of Cave City, 1 ♂ I, T.C.B. and T.G.M., VIII/23/65. (2) Diamond Cave, 2 miles N of Park City on State Rte. 225, 1 ♂ I, T.C.B., S.B.P., J.R.H., and J. F. Fitzpatrick, Jr., VII/25/64. (3) Twyman Cave, 2 miles N of Hiseville, 2 ♂ II, 2 ♀, R.M.N., IX/11/65. Christian County: (1) Glover’s Cave, 4 miles SW of Trenton, 2 ♂ II, 2 ♀, T.C.B., VI/9/57. Edmonson County: (1) Mammoth Cave, Echo River, 1 ♂ I, 1 ♂ II, 3♀, 7j ♂, 5j ♀, W.P.H., date?; 1 ♂ II, 3 ♀, L.H., VIII/30/39. 4 ♀, Raymond Nelson, VII/28/58. (2) Mammoth Cave, Roaring River, 5 ♂ I, 1 ♂ II, 5♀, 2j ♂, 4j ♀, W.P.H., XIII/28/01; 1 ♂ II, C.W.H., XI/29/63. (3) Mammoth Cave, Styx River, 1 ♂I, T.C.B., IV/28/62; 5 ♂ I, 1 ♂ II, 4 ♀, T.C.B., V/13/62. (4) Mammoth Cave, Lake Lethe, 3 ♂ I, 1 ♂ II, T.C.B., X/25/61; 1 ♂ I, T.C.B. and R.A.K., X/11/63; 5 ♀, T.C.B. and R.A.K., XI/25/61. (5) Mammoth Cave, Crystal Lake, 1 ♂ I, T.C.B., II/22/64; 1 ♂ II, T.C.B., IV/?/64. (6) Mammoth Cave, 1 ♂ I, Peter Parker, ?/?/1858; 2j ♂, Leonard Giovannoli, VII/19/29; 1 ♂ II, 3♀, 1j♀, L.G. VIII/6/29; 1 ♂ II, 4 ♀, V. E. Shelford, VII/4/42; 2j ♀, ?, VIII/28/41; 1 ♂ I, Kjell Sandved, VI/?/67; 1 ♂ I, 1 ♂ II; 2♀, 1j♀, 1j♀, W.P.H., date?; 1♀, M. E. Mann, date?; 1j♂, Ellsworth Call, date?; 1 ♂ II, 3 ♀, coll. and date (?). (7) Blowing Spring Cave in Mammoth Cave National Park, 1 ♀, L.H., XII/1/56; 1 ♀, O.D. Lee, date?. (8) Cedar Sink Cave, in Mammoth Cave National Park, 1 ♂ II, T.C.B., X/29/66. (9) Stream in Long Cave, Mammoth Cave National Park, 1 ♂ II, 1 ♀, L.H., I/5/56. (10) Stillhouse Hollow Cave, Mammoth Cave National Park, 1 ♀, L.H., XI/17/56. (11) White Cave, 3♀, John E. Younglove, date?. (12) Floyd Collins Crystal Cave, in Mammoth Cave National Park, 1 ♀, Carl Melton, V/28/60. Hart County: (1) Bald Knob Cave, 2 miles W of Hardyville, 1 ♂ II, 1 ♀ with eggs, R. M. Norton, IX/11/65. (2) Buckner Hollow Cave, 1.2 miles SE of Hinesdale, 2 ♂ I, 3 ♀, J.R.H. and T.C.B., VIII/30/63. (3) Horse (=Hidden River) Cave, in town of Horse Cave, 2 ♀, 1j ♂, 1 j ♀, E. P. Creaser and M. Becker, VIII/28/29; 1 ♀, E.P.C. and B., V/13/30; 1 ♂ I, 1 ♂ II, 1 ♀, 1j♂, L.H., VIII/30/39; 1 ♂ II, 1 ♀, Nat. Spel. Soc., VIII/29/41. (4) Stream in cave, 2 miles SW of Northtown, 1 ♂ I, 1 ♀, L.H., III/23/57. (5) Mammoth Onyx Cave on St. Rte. 335, 1 ♀, R.R., VII/16/39. Logan County: (1) Cooks Cave, 1 mile E of Adairville, 2 ♂ I, 1 ♀, T.C.B., VI/25/57. (2) Mud River Cave, 4 miles E of Russellville, 3 ♂ I, 3 ♂ II, 3 ♀, J.R.H. and T.C.B., VIII/13/65. Trigg County: (1) Cool Spring Cave, on Sinking Fork Creek, 2♂I, S.B.P. and R.M.N., IV/19/64; 4 ♂ I, 1 ♂ II, 5 ♀, S.B.P., VI/28/65. Warren County: (1) By-Pass Cave, Bowling Green, 1 ♀, K. Haas, VI/?/55. (2) Lost River Cave, 3 miles S of Bowling Green, 15j♀, D. H. Puckett and Herbert Shadowen, VIII/7/64. (3) Pruitt Saltpeter Cave, 0.8 mile SE of Anna, 2 ♂ I, 1 ♂ II, 3 ♀, T.C.B., C.W.H., and D.G.H., XI/30/64.
TENNESSEE: Montgomery County: (1) Sink Hole Cave on Austin Peay College Farm at Clarksville, 4 ♂ II, 3♀, D. A. Etnier, XI/22/68. (2) Bellamy Cave, 3.0 miles S of Oakwood, 1 ♂ II, 1 ♀, Merlin Tuttle, VIII/29/69.
RANGE.—(Figure 1) The range of Orconectes pellucidus extends southwestward from Hart County to Trigg County, Kentucky, and Montgomery County, Tennessee.
VARIATIONS.—Most stable among the features examined in Orconectes pellucidus are perhaps the secondary sexual characteristics of the adults. The first pleopods of the male uniformly exhibit a markedly slender (in lateral aspect) distal portion and a mesial process which extends distally much beyond the tip of the central projection. The hooks on the ischia of the third and fourth pereiopods vary in size, particularly that of the fourth, but are always clearly evident in the first-form male. Those on the fourth may be much smaller than those on the third, and neither greatly swollen; occasionally only the hook on the third is markedly robust; but in some males, the hooks on the two pereiopods are subequal in size, and both swollen. The annulus ventralis, while showing minor variations in outline and contour of the ventral surface, always has a rather steep, evenly curved caudal surface and lacks the caudal plateau-like rim characteristic of the other troglobites of the genus.
Whereas, there is comparatively little variation in the secondary sexual characteristics of O. pellucidus, the carapace and chela show a wide range of differences. Most of those noted in the carapace, including meristic ones, are associated with the degree of development of the spiny elements. In general, among those individuals that have a number of strongly developed cervical and hepatic spines, the marginal spines of the rostrum, the acumen, the postorbital spines, and that on the antennal scale are longer than those in specimens having reduced, and usually fewer cervical and hepatic spines (see Figure 15u, v). Inasmuch as, through convention, the length of the carapace is given as the distance between the tip of the rostrum and the midcaudodorsal margin of the carapace, it is obvious that a spiny (hence, having a longer rostrum) individual of approximately the same size as one that is relatively aspinous has a proportionately greater carapace length. The longer rostrum is also reflected in differences noted in the relative length of the areola, which is expressed in the percentage of the total length of the carapace; that is, an animal having a longer rostrum has a proportionately shorter areola. Comparing the same two illustrations mentioned above, the areolae constitute 41.4 and 38.9 percent of the carapace length, respectively, although there is only 0.1 mm difference in the actual length of the areolae of the two. Thus, the relative lengths of the areola are not so much determined by variation in its length as by the variation in the length of the rostrum, and the latter seems, for the most part, to be correlated with the greater development of the acumen (essentially a spine). Furthermore, it seems at least possible, on the basis of our limited data, that the aspinous condition may be correlated with more strongly lotic habitats.
The loss and regeneration of appendages among troglobitic crayfishes is commonplace, and the regeneration is often so complete that frequently it is difficult to determine whether or not a given cheliped is the original one or a replacement. The occasional occurrence of a comparatively robust chela on a large male elicits the conclusion that few individuals reach adulthood without having regenerated at least one member of this pair of appendages. Even with the tremendous range of variation that has been observed in them, an elongate, comparatively narrow, tuberculate palm is characteristic of all of the troglobitic species of the genus. We have been unable to discover any consistent feature of the cheliped which is unique to one of the species.
Despite the variations in spination, no particular pattern or degree of development of the spines seems to be correlated with a major portion of the range of the species. In some localities, all the specimens collected have been very spiny, and in others, the only traces of spines on the carapace are limited to a single, small cervical spine and one or two adjacent small tubercles, weak marginal spines on the rostrum, and a broad, short acumen. Yet in other localities, while one of the two types seem to predominate, both are represented in the population. Further, to make more difficult correlation with a portion of the range of the species or with ecological factors, there is considerable variation in the degree of development of the individual spines, so that two specimens from the same or different localities may have virtually an identical number of spines, but in one they are very prominent and in the other comparatively weak.
From the eastern portion of the range in Barren, Edmonson, and Hart counties, we have 131 specimens from 15 localities. In Hart County, only in Horse Cave are there specimens which might be classified as spiny (Figure 15a), but even there, only 3 of the 15 specimens could be so designated. The others have very weak spines, or the hepatic spines are reduced or lacking (Figure 15d). Among them the areola constitutes from 38.5 to 40.6 percent of the length of the carapace. A single specimen from Floyd Collins Crystal Cave has a large number of small spines, and its areola constitutes 38.6 percent of the carapace length. From Buckner Hollow Cave (Figure 15b) are 5 specimens, of which 3 are almost smooth, and only 1 moderately spiny; their areolae range from 39.1 to 41.1 percent. The remaining 5 specimens from Bald Knob Cave, Mammoth Onyx Cave, and the unnamed cave two miles southwest of Northtown (Figure 15c) have few poorly developed spines, and the areola ranges from 39.6 to 41.7 percent of the carapace length.
In Edmonson County, the range of variation in the 95 specimens from Mammoth Cave is almost as great as that from all the other caves in the county combined (Figure 15e-k), and the areola ranges from 38.0 to 41.6 percent of the total length of the carapace. Our 3 specimens from White Cave are comparatively spiny (Figure 15n) and their areolae constitute 38.9 to 40.4 percent of the carapace length. In the remaining localities, the 5 available specimens are relatively aspinous (Figure 15l, m, o), and their areolae vary from 39.7 to 42.4 percent of the carapace length.
The collection from Twyman Cave, Barren County, consists of 3 very spiny individuals (Figure 15v), and 1 which is almost spineless, resembling the 3 specimens from Diamond Cave and Cave City Cave (Figure 15t, u). In the specimens from the former cave the areola ranges from 38.5 to 40.5 percent of the carapace length, and in the latter two, 41.8 and 41.4 percent, respectively.
In the central portion of the range, in Warren and Logan counties, a similar range of variation exists. Among 6 specimens from Pruitt Saltpeter Cave and 15 specimens from Lost River Cave, both moderately spiny and aspinous (Figure 15q-s) individuals are present in which the areola comprises 38.9 to 41.3 percent of the length of the carapace. Our single specimen from By-Pass Cave is aspinous (Figure 15p), with the areola constituting 40.5 percent.
In Logan County, the 3 specimens from Cooks Cave are very weakly spined (Figure 16b, c), with areolae constituting 38.1 to 39.9 percent of the carapace length. In contrast, the 9 specimens from Mud River Cave are more spiny (Figure 16a) and, except for the largest first-form male, which has an areola comprising 40.6 percent of the carapace length, they exhibit a range of 37.6 to 39.8 percent.
In the three caves in the southwestern part of the range there is essentially a repetition of what exists elsewhere. Our 4 specimens from Glover Cave, Christian County, are relatively smooth (Figure 16d) and have areola constituting 39.6 to 41.6 percent of the carapace length. The 12 specimens from Cool Spring Cave, Trigg County, are among the most spiny specimens (Figure 16e) we have observed, and their long acumen is reflected in the relative areola length which ranges from 37.6 to 38.7 percent of the carapace length. None of the 9 specimens from Montgomery County, Tennessee is so spiny as those from Cool Spring Cave, and considerable variation exists among them, as might be assumed by the range of their relative areola length, 39.3 to 44.2 percent of the carapace length.
- bibliographic citation
- Hobbs, Horton Holcombe, Jr. 1972. "Origins and Affinities of the Troglobitic Crayfishes of North America (Decapoda, Astacidae) II Genus Orconectes." Smithsonian Contributions to Zoology. 1-84. https://doi.org/10.5479/si.00810282.105
Comprehensive Description
provided by Smithsonian Contributions to Zoology
Orconectes pellucidus (Tellkampf)
Krebse.—Anonymous, 1843a:49.
Astacus Bartoni?.—Anonymous, 1843b:175 [not Fabricius, 1798:407].—Putnam, 1872:10.—Hobbs and Barr, 1972:59, 60.
Astacus pellucidus Tellkampf, 1844a:684; 1844b:383; 1845:85.—Erichson, 1846:87, 89.—Gibbes, 1850:195.—Dana, 1852a: 522.—Newport, 1855:164, 165, figs. 11–14.—Lucas, 1864:iv.—Hagen, 1870:6, 7, 11.—Faxon, 1885a:10.—R. Rhoades, 1944:112; 1959:399.—Holthuis, 1956b:116.—Hobbs and Barr, 1972:1, 42, 59, 60, 64.
Cray-fish.—W. M. Thompson, 1844:111–112.
astacus pellucidus.—Tellkampf, 1845:93.
Astacus (Cambarus) pellucidus.—Erichson, 1846:95–96.
Craw-fish.—Silliman, 1851:336.
Cambarus pellucidus.—Girard, 1952:87, 88.—Hagen, 1870:8, 27, 30–34, 55–56, 97, 101, pl. 1: figs. 68–71, pl. 3: fig. 148, pl. 6; 1872:494–495.—Packard, 1871:750, 751, fig. 131; 1872b:17, 18, fig. 131; 1873:94 [in part]; 1874:209; 1879:315, fig. 268; 1886:295–297, figs. 263, 264; 1888:8, 10, 12, 19, 38–42, 82, 86, 110, 111, 119, 122, 123, 125, 127 [in part]; 1890:393 [in part].—Cope, 1872a:410; 1879:495.—Smith, 1874:639 [in part]; 1875:477 [in part].—Putnam, 1875a:222; 1875b:198; 1877:16–19.—Hubbard, 1880:38.—Joseph, 1882:12.—Leydig, 1883:38–40.—Faxon, 1884:139–140 [in part]; 1885a:4, 5, 7–9, 11, 16, 18, 19, 40–46, 59, 82–84, 111, 158, 169, 174, 178, 179 [in part]; 1885b:358; 1890:626, 628; 1898:647 [in part]; 1914:415 [in part], pl. 7: fig. 2a–c.—Underwood, 1886:371 [in part].—Garman, 1889:235, 236; 1924:88, 89.—Parker, 1890:153–155, 157–161, pl. 1: figs. 2–6.—Hovey, 1891:72; 1912:80, 81, 108, 109, 115, 119, 124, 2 figs.—Ortmann, 1892: 11 [in part]; 1902:277–279 [in part]; 1905a:92, 95, 96 [in part]; 1918:838, 848 [in part].—Cunningham, 1893:537.—Stebbing, 1893:208.—Lönnberg, 1894:126; 1895:4–6, 9.—Hay, 1896:485 [in part]; 1897:208–209 [in part]; 1899:959, 966 [in part]; 1902a:226, 228, 230, 235 [in part]; 1902b:436.—Call, 1897:103, 104; 1901:103, 104.—Eigenmann, 1899:60; 1903:169 [in part].—?Price, 1900:155.—Steele, 1902:7, 16, 18 [in part].—Harris, 1903a:602, 606; 1903b:58, 67, 70, 80, 112–118, 151, 153, 157, 162, 167 [in part].—Bell, 1906:300, 304, 305.—Banta, 1907:69–73, 102, 103 [in part].—Graeter, 1909:470 [in part].—Osborn, 1912:923 [in part].—Spurgeon, 1915: 385–394 [in part].—Pratt, 1916:392 [in part], fig. 623; 1935:455 [in part], fig. 623; 1948:455 [in part], fig. 623.—Borradaile, 1923:262, fig. 279.—Spandl, 1926:95, 141–142, 148 [in part].—Calman, 1927a:51.—Stiles and Hassell, 1927:219 [in part].—Chappuis, 1927:91, 120 [in part].—Creaser, 1931:10; 1932:336.—Giovannoli, 1933a:618–619, fig. 90; 1933b:236–237, fig. 90.—Wolf, 1934:104–105 [in part].—Park, 1938:209.—Mohr, 1939:202.—R. S. Fleming, 1939:304, 305.—Bouvier, 1940:68.—Park, Roberts, and Harris, 1941:154–171, figs. 1–5.—R. Rhoades, 1941:141, 142, 144.—Hobbs, 1942a:335, 338, 342, 351, 352 [in part]; 1967a:125.—Dearolf, 1942:50; 1953:228–229.—Jeannel, 1943:30, 31, 53, 272, 279.—Balss, 1944:402; 1955:1311, 1312.—Jeannel and Henrot, 1949:21.—Allee, et al., 1949:559, fig. 196.—Bott, 1950:25.—Hobbs and Barr, 1960:19; 1972:37–39, 50, 51, 58, 60–63 [in part].—Vandel, 1964:448, 453, 461, 501, fig. 76; 1965:383, 391, 423, 424, fig. 76.—Jegla and Poulson, 1968:280.—Husson, 1970:108.
Crabs.—Darwin, 1859:137.—Hobbs and Barr, 1972:60.
Eyeless Crabs.—Binkerd, 1869:86.—Hobbs and Barr, 1972:60.
Cambarus pelulcidus.—Hagen, 1870:106 [erroneous spelling].
Orconectes pellucidus.—Cope, 1872a:409, 419; 1872b:161, 162, 173, 174; 1879:492, 494 [in part].—Cope and Packard, 1881: 879, 881, 882 [in part].—Wright, 1884:272, 273.—Packard, 1888:24–25, 126, 140, 155[?], pl. 21: fig. 2[?], pl. 22: fig. 7[?]; 1894:735.—Hobbs, 1948a:19; 1967a:125, 130; 1967b:12 [in part]; 1972b:77, 149, figs. 11b, 60a; 1974b:37–38, fig. 102.—Pennak, 1953:458 [in part].—Lübke, 1953, fig. 110.—Eberly, 1954:59; 1958:1–6 [in part]; 1960:29–32 [in part].—Wells, 1959:5–7.—Barr, 1960:5 [in part]; 1967a:160, 161, 186, 187, 192, pl. 46; 1967b:480; 1968:65, 91, fig. 18.—F. A. Brown, 1961:929–930.—Creaser, 1962:3 [in part].—R. Rhoades, 1962:68, 69, 79, 94 [in part].—Fitzpatrick, 1963:60; 1967:141, 142.—Holthuis, 1964:42, 43, 45, 47.—Fingerman, et al., 1964:415, 420.—Vandel, 1964:448, 509, 570, 575 [in part]; 1965:379, 429, 483, 486 [in part].—Mohr, 1964:828.—Poulson, 1964:752, 756, 757, 759, 762, 764; 1966:15.—Moore and Nicholas, 1964:71, 88 [in part].—Frey, 1965:623, 624 [in part].—Mohr and Poulson, 1966:166, 204 [in part].—[?]D. H. Thompson, 1967:46, 47, 51.—Culver, 1967:34.—Jegla and Poulson, 1968:280.—Cooper and Poulson, 1968:130, fig. 8.—Poulson and Smith, 1969:199–201.—Poulson and Jegla, 1969:193–195.—Anonymous, 1970:120.—Barr and Kuehne, 1971:71, 72.—Hobbs and Barr, 1972:1, 2, 4, 5, 8–14, 22, 37–43, 50, 52, 58–72, 81–83 [in part], figs. 1, 14–16.—Hobbs III and Burdsall, 1972, cover, 4 [in part], fig. 1.–D. G. Hart and C. W. Hart, 1974:71, 74, 116, 136.—Hobbs III, 1975:276, 280, 296, fig. 2.
Crayfishes.—Putnam, 1875b:191.
Astacidae.—Shaler, 1875:361 [1876:10].—Hobbs and Barr, 1972:60.
Cray fish.—Shaler, 1875:362–363 [1876:11, 12].
Blind Craw-fish.—Packard, 1879, fig. 269.
Cambarus typhlobius Joseph, 1880:202 [type-locality: Krain (= Carniola, now northern Yugoslavia), in error, see pp. 8–9 herein].—Faxon, 1884:139; 1885a:7, 45–46; 1914:427.—Underwood, 1886:373.—Hay, 1896:477.—Harris, 1903b:131, 151.—Bouvier, 1940:68.—Van Straelen, 1942:2.—Bott, 1950:25.—Villalobos F., 1953:348; 1955:11.—Holthuis, 1964:42–47.—Hobbs and Barr, 1972:1, 61–64.
Cambarus stygius Joseph, 1881:241, 249 [nomen nudum] [not Bundy, 1876:3]; 1882:12 [homonym].—Cope, 1881:882.—Underwood, 1886:373.—Packard, 1888:86, 119, 123, 130.—Faxon, 1914:427 [in part].—Léger, 1924:1206.—Spandl, 1926:95.—Chappuis, 1927:90, 91.—Stammer, 1932:608.—Wolf, 1934:105.—Bouvier, 1940:68.—Jeannel, 1943:271, 272.—Holthuis, 1964:42–45, 47.—Hobbs and Barr, 1972:1, 52, 61, 63, 64.
Blind Krebse.—Joseph, 1881:237.
Cambarus coecus Joseph, 1881:237 [nomen nudum].—Faxon, 1884:139; 1885a:7, 45; 1914:427.—Bouvier, 1940:68.—Holthuis, 1964:42, 45.—Hobbs and Barr, 1972:1, 61, 63, 64.
Blind crayfish.—Semper, 1881:77.—Packard, 1894:742.—Call, 1901:101.—Holt, 1968:87.—Hobbs and Barr, 1972:62.
Cambarus (Orconectes) pellucidus.—Hovey, 1882:222 [in part].—Hobbs and Barr, 1972:37, 61 [in part].
Orconectes.—Hovey, 1882:223 [in part].—Barr, 1968:85 [in part].—Barr and Kuehne, 1971:72, 85, 86.
Cambarus Stygius.—Faxon, 1884:139; 1885a:iii, 6, 7, 45, 46 [in part].—Bott, 1950:25.
Camtarus (Orconectes) pellucidus, form inermis.—Packard, 1888:156, pl. 27: fig. 5 [erroneous spelling].—Hobbs and Barr, 1972:61.
Astacus Cambarus pellucidus.—Rabé, 1890:9.—Hobbs and Barr, 1972:62.
Astacus Cambarus Stigius.—Rabé, 1890:9 [erroneous spelling].—Hobbs and Barr, 1972:62.
Cambarus.—Apfelbeck, 1895:24.—Bolivar and Jeannel, 1931:306, 307, 309.—Vandel, 1964:494, 495, 512; 1965:418, 419, 433.—Hobbs and Barr, 1972:62.
Colorless crawfish.—Proctor, 1898:658.
Cambarus pelucidus.—Eigenmann, 1900:228 [erroneous spelling].
Cambrus pellucidus.—Price, 1900:155 [erroneous spelling].
Crayfish.—Call, 1901:100.—Hobbs and Barr, 1972:60, 61, 63, 64.
Cambarus (Faxonius) pellucidus.—Ortmann, 1905a:97, 107, 108, 111, 114 [in part]; 1905b:435 [by implication]; 1931:64–65 [in part].—Pearse, 1910:10.—Fage, 1931:373 [in part].—Turner, 1935:876.—Hart, 1962:121.
Blind Crayfish.—Calman, 1927b:53.
Cityphlobius.—Joleaud, 1939, pl. 14 [lapsus calami for C. typhlobius].—Van Straelen, 1942:2.
Cambarus caecus.—Bouvier, 1940:68 [erroneous spelling].
Cambarus (Fexonius) pellucidus.—Rioja, 1941:193 [erroneous spelling].
Cambarus pellucidus pellucidus.—R. Rhoades, 1941:144.—Hobbs and Barr, 1972:51.
Cambarus pelludicus.—Dearolf, 1942:50 [erroneous spelling].
Crawfish.—Dearolf, 1942:52.
Orconectes (Orconectes) pellucidus pellucidus.—Hobbs, 1942b:154 [by implication].
Cambarus Pellucidus.—Jackson, 1942:4.
Orconectes pellucidus pellucidus.—Hobbs, 1942a:352 [by implication]; 1948a:19, 20, figs. 7, 12; 1967a:131; 1967b:7.—R. Rhoades, 1944:112, 113, 115, 117, 120–121; 1959:401; 1962:68, 90 [in part], fig. 8.—Cole, 1959:81.—Eberly, 1960:30.—Hobbs and Barr, 1960:19; 1972:22, 40, 42, 51, 63, 64.—Nicholas, 1960:133.—Barr, 1961:32; 1968:60.—Hart and Hobbs, 1961:176, 178, 180, 184.—Wolfe and Cornwell, 1964:1467, 1468.—Frey, 1965:624 [in part].—Jegla, Poulson, and Cooper, 1965:639.—C. W. Hart and D. G. Hart, 1966:8, 9; 1969:167.—Jegla, 1966:346–347, 353.—M. R. Cooper, 1969:205.—D. G. Hart and C. W. Hart, 1974:115.
Orconectes pellucidus pelluicdus.—Hobbs, 1948a:16 [erroneous spelling]
Orconectes pellucidus pellucidus pellucidus.—Hobbs, 1948a:19 [lapsus calami].
Cambarus Coecus.—Bott, 1950:25.
Cambarus (Cambarus) pellucidus.—Balss, 1955:1311.—Hobbs and Barr, 1972:63.
Gambarus typhlobius.—Croizat, 1958:908 [erroneous spelling].
Orconectes (Orconectes) pellucidus.—Hobbs, 1959:890 [in part].—Hobbs and Barr, 1972:12, 51, 64 [in part].
Crayfishes.—Barr, 1964:79; 1966:15.
Orconectes pellucidus subspecies.—Hobbs and Barr, 1972:14 [in part].
Albinistic crayfishes.—Hobbs and Barr, 1972:60 [in part].
DIAGNOSIS.—Hobbs and Barr (1972:65–66):
Albinistic, eyes reduced and without pigment; rostrum with marginal spines or tubercles delimiting base of acumen…postorbital ridges usually terminating cephalically in spines or tubercles; hepatic area with or without two to many spines; at least one, often several cervical spines or acute tubercles present; areola 3.7 to 6.0 times longer than broad and constituting 34.1 to 42.2 percent of entire length of carapace…hooks on ischiopodites of third and fourth pereiopods. First pleopod of first-form male with greatest cephalocaudal diameter of pleopod more than twice that immediately proximal to base of central projection, always terminating in only two elements; noncorneous mesial process broad basally, triangular, directed distally and slightly caudally and extending considerably beyond distal extremity of central projection, frequently almost obscuring latter in caudal aspect…; central projection small, corneous, flattened in cephalocaudal plane, and directed distad; slight swelling at cephalic base of central projection.
SIZE.—Carapace length 39.1 mm; postorbital carapace length 31.8 mm.
TYPES.—Holotype, ZBM 1562 ( I).
TYPE-LOCALITY.—Mammoth Cave, Edmonson County, Kentucky, U.S.A.
RANGE.—U.S.A. Orconectes pellucidus is known from the karst area (Pennyroyal Plateau) extending southwestward from Hart County to Trigg County, Kentucky, and Montgomery County, Tennessee.
The following localities, unless accompanied by references or collectors and/or dates, were taken from Hobbs and Barr (1972:68–69).
Kentucky. Barren County: (1) Cave City [= Railroad Cave], in town of Cave City; (2) Diamond Cave, 2 mi (3.2 km) N of Park City on State Rte. 225 (Packard, 1888:39); (3) Twyman Cave, 2 mi (3.2 km) N of Hiseville; (4) Parker Cave, 1.8 mi (2.9 km) SW of Park City, 4 Aug 1975, sight record by J. R. Holsinger. Christian County: (5) Glover's Cave, 4 mi (6.4 km) SW of Trenton. Edmonson County: (6) Mammoth-Flint Ridge Cave System (including Echo River, Roaring River, Styx River, Lake Lethe, Crystal Lake, Floyd Collins Crystal Cave) (Anonymous, 1843a:49); (7) Blowing Spring Cave in Mammoth Cave National Park; (8) Cedar Sink Cave in Mammoth Cave National Park; (9) Long Cave in Mammoth Cave National Park; (10) Stillhouse Hollow Cave in Mammoth Cave National Park; (11) White Cave (Faxon, 1885b:358); (12) Bat Cave, exact location unknown (Packard, 1888:40); (13) ?Ganter's Cave [= Blind Fish Cave, “down the Green River from Mammoth Cave”] (Putnam, 1875b:198); (14) Martin Cave, exact location unknown. Hart County: (15) Bald Knob Cave, 2 mi (3.2 km) W of Hardyville; (16) Buckner Hollow Cave, 1.2 mi (1.9 km) SE of Hinesdale; (17) Horse Cave [= Hidden River Cave], in town of Horse Cave (R. Rhoades, 1944:120); (18) Cave 2 mi (3.2 km) SW of Northtown; (19) Mammoth Onyx Cave on State Rte. 335 (R. Rhoades, 1944:120); (20) Cartmill Cave, 25 mi (4.0 km) E of Northtown, 27 Nov 1972, H.H.H. III, coll.; (21) Krump Spring Cave, 2 mi (3.2 km) ESE of Northtown, 1973, B. Ransom(?), coll. Logan County: (22) Cooks Cave, 1 mi (1.6 km) E of Adairville; (23) Mud River Cave, 4 mi (6.4 km) E of Russellville. Trigg County: (24) Cool Spring Cave on Sinking Fork Creek. Warren County: (25) By-Pass Cave, Bowling Green; (26) Lost River Cave, 3 mi (4.8 km) S of Bowling Green; (27) Pruitt Salt Peter Cave, 0.8 mi (1.3 km) SE of Anna; (28) Graham Spring Cave, 6 mi (9.7 km) ENE of Bowling Green, 21 Oct 1972, H.H.H. III, coll.
Tennessee. Montgomery County: (29) Sink Hole Cave on Austin Peay College Farm at Clarksville; (30) Bellamy Cave, 3.0 mi (4.8 km) S of Oakwood, lat. 36°29′39″N, long. 87°34′14″W.
ECOLOGICAL
- bibliographic citation
- Hobbs, Horton Holcombe, Jr., Hobbs, Horton Holcombe, III, and Daniel, M. A. 1977. "A Review of the Troglobitic Decapod Crustaceans of the Americas." Smithsonian Contributions to Zoology. 1-183. https://doi.org/10.5479/si.00810282.244
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