Larval taxonomy of some Australian stonefly species (Plecoptera: Gripopterygidae)

Submission note: A thesis submitted in total fulfilment of the Doctor of Philosophy to the School of Life Sciences, College of Science, Health and Engineering, La Trobe University, Albury-Wodonga.

Thesis with publications.

This thesis explores the taxonomy of the Family Gripopterygidae in Australia with focus on the taxonomy of the larval life-stage. A large disparity exists in the knowledge of larval forms when compared to the adult taxonomy with 51% of gripopterygid species having undescribed larva. The importance of stoneflies (Plecoptera) as an indicator group for monitoring aquatic ecosystems means knowledge of the larval taxonomy and the ability to identify species is essential. This thesis explored using morphological and molecular methods for species delimitation within the Family Gripopterygidae which is the largest family of stoneflies in Australia. These studies focussed on the association of life-stages and in particular increasing our knowledge of larval morphology which meant a descriptive approach was necessary. The combined use of morphology, geography, reverse taxonomy and molecular data showed a robust biological and ecological basis for the definition of species as presented in this thesis. The results highlighted that when using molecular data, in particular a distance-based sequence divergence, for species delimitations there is often a large intra-specific variation shown within the COI gene. This affects the ability to use a strict COI barcode species concept which is important to understand as advancements are made towards molecular based environmental monitoring that often relies on an arbitrary cut-off for specific naming. The combination of molecular and morphological methods enabled the larval morphology to be reassessed and has led to the following outcomes: two new genera (Oedemaperla and Odontoperla with 3 new combinations) and 5 new species (Newmanoperla theischingeri, Leptoperla tsyrlini, Dinotoperla aryballoi, Dinotoperla tasmaniensis and Oedemaperla shackletoni); the first formal generic larval description for Newmanoperla; updated descriptions for larvae of 37 species; and a dichotomous key to larvae for Newmanoperla, Dinotoperla, Oedemaperla and Odontoperla. This comprises a reassessment of 30% of the Australian Gripopterygidae fauna.