Comprehensive Description

provided by Smithsonian Contributions to Zoology
Pericompsus metallicus Bates

Pericompsus metallicus Bates, 1871a:246. [Lectotype, here selected, a male, in MHNP. One paralectotype also labeled by me in MHNP. Type-locality: “Rio Janeiro,” Brazil.]

Tachys mendocinus Jensen-Haarup, 1910:553. [Lectotype, here selected, a male, in ZMC. Five paralectotypes also labeled by me in ZMC. New synonymy. Type-locality: Mendoza Province, Argentina.]

Leiotachys humeralis Jeannel, 1962:615. [Holotype, a female, in MHNP. New synonymy. Type-locality: Central Chile.]

DESCRIPTION.—Form (Figure 27): Similar to P. brasiliensis, but easily distinguished from members of that species by the presence of a sixth row of punctures on the elytron.

Color: Venter mostly piceous; forebody dorsally darker than elytra, both rufopiceous.

Head: Narrower across eyes than pronotum; frontal furrows deeply impressed and evenly arcuate to posterior margin of eye; eyes large and prominent.

Pronotum (Figure 27): Broadly transverse; sides shallowly sinuate in basal half; base slightly lobed medially; hind angles acute, slightly prominent, side margins slightly reflexed; disc moderately convex.

Elytra: Each elytron with 6 punctate interneurs; punctures moderately small and separated longitudinally by about their own diameter; rows 2–6 effaced in apical third, row 1 entire, striate at apical third, interneur 7 effaced externally throughout; interneur 8 well impressed throughout, not foveate; humeral margin rounded and nearly straight to level of interneur 4, not connected to base of 4; side margin narrowly explanate, coarsely serrate-setulose in basal fourth; chaetotaxy as in P. brasiliensis; plica long and well developed externally.

Microsculpture: Effaced from dorsal surface.

Genitalia: Male (Figure 32) (9 examined); female characteristic of ephippiatus group (examined).

Size: Length, 2.20–2.60 mm; width, 0.92–1.08 mm; 10 specimens measured.

VARIATION.—The width of the pronotum varies within population samples relative to the width of head and elytra.

NATURAL HISTORY.—Specimens were collected from January through June and in September and December. No dated specimen was teneral.

DISTRIBUTION.—The range of this species extends from 4° N latitude to 35° S latitude in South America. Most specimens have been collected adjacent to the Tropic of Capricorn, with two disjunct sites farther north also yielding specimens.

LOCALITY RECORDS (Figure 46).—I have seen 52 specimens from the following localities:

SOUTH AMERICA: ARGENTINA: (MCZ); Buenos Aires Province, Buenos Aires (KWCo), Isla de Santiago near La Plata (MCZ), San Fernando (USNM); Mendoza Province (ZMC), Cerro Quada (USNM); Salta Province, Salta (USNM); San Jaun Province, Jachal (JNeg); Santiago del Estero Province, Anatuya (USNM); Province unknown, “Cap ?ferspuerto” (USNM). BOLIVIA: Santa Cruz Department, Cambeiti (USNM), El Cidral about 100 kilometers northeast of Santa Cruz (MCZ), Los Huesos (USNM). BRAZIL: Mato Grosso State, Corumba (MCZ, USNM), Rio Caraguata (MCZ, USNM); Pernaumbuco State, Palmares (USNM); Rio de Janeiro State, Rio de Janeiro (MHNP). CHILE: “Central Chile” (MHNP). COLOMBIA: Huila Department, Villavieja (CAS). PARAGUAY: Amambay Department (MCZ). URUCUAY: Montevideo Department, Montevideo (USNM).
bibliographic citation
Erwin, Terry L. 1974. "Studies of the subtribe Tachyina (Coleoptera: Carabidae: Bembidiini), Part II: A Revision of the New World-Australian Genus Pericompsus LeConte." Smithsonian Contributions to Zoology. 1-96. https://doi.org/10.5479/si.00810282.162