AbstractsBiology & Animal Science

Systematics of the Conoesucidae, Helicophidae, Calocidae and Antipodoeciidae (Insecta:Trichoptera), with emphasis on the immature stages

by Jean Elizabeth Jackson

Institution: University of Tasmania
Year: 1991
Keywords: Caddisflies; Caddisflies
Record ID: 1032519
Full text PDF: http://eprints.utas.edu.au/20313/1/whole_JacksonJeanElizabeth1992_thesis.pdf


The systematics of the trichopteran families Conoesucidae, Helicophidae, Calocidae and Antipodoeciidae was investigated, with particular emphasis on immature stages (larvae and pupae). Study of Antipodoeciidae was limited to its inclusion in phylogenetic analysis, due to lack of material. Collecting was carried out throughout Tasmania to establish the species to be included in these families and their distribution. Immatures were associated with adults by rearing for all the conoesucid species, 3 of the 6 helicophids and 2 of the 5 calocids known from Tasmania. Larvae and pupae are described and keys to species given. Two new species of Conoesucus are described. Univariate morphometric analysis of male genitalia of Lingora vesca and L. aurata showed that L. vesca is a variant of L. aurata, and is therefore synonymised with it. Electrophoretic data showed Conoesucus adiastolus sp. n. to be distinct from the morphologically similar C. brontensis. Morphometric analysis of wing venation enabled adults of Conoesucus brontensis, C. nepotulus and C. adiastolus to be separated, but with some overlap; measurement of male maxillary palps showed that males could be reliably identified by their structure. Species distribution within Tasmania falls into two categories: those restricted to the west, and those species which are widespread. The 12 western species are all endemics; of the ten widespread species, at least six are shared with the mainland. More detailed study of mainland species is required before detailed biogeographic hypotheses explaining the entire Australian distribution of these families can be proposed. Chromosomes were counted in all the species for which immatures were identified. Chromosome number varied between families: for Conoesucidae n=25, Calocidae (Caenota and Tamasia) n=22, Helicophidae (Alloecella) n=32-40. 4, Although the number for Alloecella could not be determined precisely, it is tRlughest so far recorded for Trichoptera. Chromosomes were too small and uniform for other characteristics to be studied with the method used. These results are discussed in relation to placement of the families within Trichoptera, and chromosome evolution in Trichoptera and the sister order Lepidoptera. Phylogenetic analysis based on larval and pupal characters (including case characters) was carried out for a) the 22 Tasmanian taxa studied in detail and b) the Tasmanian species plus Antipodoecia and species of Conoesucidae, Calocidae and Helicophidae from New Zealand and South America. Analysis of Tasmanian taxa resulted in groups generally in agreement with the existing classification. Monophyly was demonstrated for the Tasmanian Conoesucidae, Helicophidae (Alloecella) and the Calocidae studied. The genera Lingora, Nampa and Matasia were shown to constitute a monophyletic group, providing evidence in support of congeneric status, although this conflicts with some characters of adults. In analysis of all taxa, New Zealand species were grouped with Australian confamilials. Groups outside the Conoesucidae were…