Agathiphaga - especially A. vitiensis - have been very important for our understanding of early Lepidoptera evolution.The Kauri moths seem to be a ‘morphological link’ between Lepidoptera and their closest relatives, the caddis-flies.Many aspects of the Kauri moths’ morphology are primitive including:
- head morphology - especially the mouthparts
- wing venation
- male genitalia
These aspects are so primitive that Kauri moths are considered 'living fossils' - they give us a clear idea of what the earliest Lepidoptera looked like.In other aspects, however, the Kauri moths are so specialised they do not resemble any other known Lepidoptera or caddis fly (living or extinct). Specialised features include:
- wing vestiture
- pre-genitalia abdomen
- musculature of the female terminal abdomen
Detailed morphological and anatomical studies of Kauri moths (particularly A. vitiensis), along with comparisons to other Lepidoptera and caddis-flies, have helped scientists understand Lepidoptera evolution better. This includes evolution of the lineage that gave rise to both caddis flies and Lepidoptera.
The Fiji kauri moth, Agathiphaga vitiensis, is found in the south western Pacific from Fiji in the east through Vanuatu and the New Hebrides to the Solomon Islands in the north and New Caledonia in the west.Kauri moths are medium-sized micro moths with a wingspan up to 27mm. The adults are brownish with a broad head and slender antennae.They rest with their wings held roof-like over the body and have a distinctive caddis fly-like appearance.Infestations of Kauri moth larvae in Kauri pine cones can sometimes reach pest levels and have negative effects on commercial production of Kauri timber - especially Pacific Kauri, Agathis macrophylla, on Fiji and the Solomon Islands.The Museum has played an important role in studies of Agathiphaga vitiensis. Our current micro Lepidoptera curator Mr Kevin Tuck, and Museum scientist the late Dr Gaden S Robinson, raised a number of adult specimens from infested Kauri seeds in the 1970s.This unique material has formed the basis for several important studies carried out by international researchers in several countries.
Agathiphagidae are 1 of only 3 lineages of Lepidoptera that have retained biting mouthparts instead of the coilable proboscis that is so distinctive for the remainder of the order.Very little is known about the biology of adult Kauri moths as they are only rarely observed in their natural habitat.They are nocturnal, and adults are thought to emerge and lay eggs in the southern hemisphere spring.Despite the functional mandibles, it is unclear whether the adults feed at all.
The eggs and egg-laying behaviour of Kauri moths have not been described.Based on the morphology of the female ovipositor - which is extendable but not piercing - we assume eggs are laid below the scales of the female Kauri Pine cone (genus Agathis).The larva feeds and subsequently pupates inside the seed of the cone.Before emerging, the larva enters a diapause that may last up to 12 years - the diapause is terminated by periods of high moisture, such as heavy tropical rain.