''Rakiura'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Trichoptera The caddisflies, or order Trichoptera, are a group of insects with aquatic larvae and terrestrial adults. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the b ...

(caddisfly). The genus contains only one

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

, ''Rakiura vernale'', which is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. ''Rakiura vernale'' represents the most basal taxon within the

Helicopsychidae Helicopsychidae (snail-case caddisflies) are a family of Trichoptera. The name refers to the helix shaped larval cases and they should not be confused with Limnephilidae which sometimes inhabit the snail shells. Their shells range from and are c ...

Identification

Larvae have a case that is dextrally coiled, with the coils incompletely fused. The head, in dorsal view, is rounded with marginal

carina Carina may refer to: Places Australia * Carina, Queensland, a suburb in Brisbane * Carina Heights, Queensland, a suburb in Brisbane * Carina, Victoria, a locality in Mildura Serbia * Carina, Osečina, a village in the Kolubara District ...

and covered by loosely distribute

setae In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. Th ...

. The posterior part of frontoclypeal is slender. In lateral view, the head is dorsally straight with eyes erected dorsad. Larvae have a strongly sclerotized

pronotum The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum ( dorsal), the prosternum (ventral), and the propleuron (lateral) on e ...

with anterior-pointing megasetae. The

mesonotum The mesothorax is the middle of the three segments of the thorax of hexapods, and bears the second pair of legs. Its principal sclerites (exoskeletal plates) are the mesonotum (dorsal), the mesosternum (ventral), and the mesopleuron (lateral) on ...

and

metanotum The metathorax is the posterior of the three segments in the thorax of an insect, and bears the third pair of legs. Its principal sclerites ( exoskeletal plates) are the metanotum (dorsal), the metasternum (ventral), and the metapleuron (lateral) ...

are weakly sclerotized. No

abdominal The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. ...

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

are present. An anal claw is present with a single row of comb-shaped accessory hooks. Adults have 2-jointed

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The t ...

palps Pedipalps (commonly shortened to palps or palpi) are the second pair of appendages of chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to the chelicerae ("jaws") a ...

, a basal joint with strong median setae, and a distal joint about 2,5 times longer than basal joint. Antennae are about as long as the fore wing. Adults have large, oval cephalic warts with an irregular median margin. Small postantennal warts are also present. Pronotum has a pair of oblong central warts. Mesonotum has setal warts divided into row of setal bases; setal warts are absent on metanotum. No postcutellar line present. Dimorphic fore wings with modifications are present only on males.

References

* Johanson, K. A. (1998). Phylogenetic and biogeographic analysis of the family Helicopsychidae (Insecta: Trichoptera). ''Entomologica scandinavica Supplement'' No.53. ISSN 0105-3574. * Johanson, K. A. (2002). Systematic revision of American Helicopsyche of the subgenus Feropsyche (Trichoptera: Helicopsychidae). ''Insect Systematics & Evolution'' (earlier: ''Entomologica scandinavica Supplement'') No.60. ISSN 0105-3574. * Johanson, K. A. (2003). Revision of the Neotropical caddisfly subgenus Helicopsyche (Cochilopsyche) (Trichoptera: Helicopsychidae), with descriptions of twelve new species. ''Insect Systematics & Evolution'' 34: 381-414. ISSN 1399-560X. * Johanson, K. A. (2001). Phylogenetic and biogeographical analysis of the New Zealand Helicopsyche von Siebold (Trichoptera: Helicopsychidae). ''Insect Systematics & Evolution'' 32: 107-120. ISSN 0013-8711. Endemic fauna of New Zealand Integripalpia Endemic insects of New Zealand {{Trichoptera-stub