Lineage to landscape : systematics and evolution of Asian camel crickets (Rhaphidophoridae) : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Conservation Biology at Massey University, Manawatū, New Zealand

Abstract

Rhaphidophoridae (camel crickets) comprises nine subfamilies, with three subfamilies and over half of the global diversity found in Asia. Our current understanding of phylogenetic relationships and the evolutionary history of Asian rhaphidophorid lineages remain significantly underexplored. My thesis addresses this gap by investigating the systematic, phylogenetic, and population structures of Asian lineages, leveraging the least explored Himalaya region with additional representatives from the Pacific (Japan, Solomon Islands, and New Zealand) for comparison. Morphological traits and mitochondrial DNA Cytochrome Oxidase I (COI) were used for systematics and phylogeographic analysis of cave associated camel crickets, while whole mitochondrial genome sequences were used to infer phylogeny and timing of the radiation of Asian lineages. I discovered and described nine new species from Eastern Bhutan. My findings indicate that (1) true species diversity of Rhaphidophoridae in the Himalayan region is undoubtedly much higher, considering my discoveries were from a small area of the full territory; (2) the two subfamilies, Rhaphidophorinae and Aemodogryllinae, that overlap in Asia potentially diverged through a series of dispersal events from Gondwana to South East Asia, rather than from walking over the Bering land bridge as previously hypothesized; and (3) the high level of genetic differentiation observed among populations of cave associated camel crickets suggest that they might be primarily cave dwellers potentially limited by climatic, biological and geophysical factors during the Pleistocene. Overall, this study provides an insight into lineage to landscape history of least explored groups of species from underrepresented regions. In conclusion, Asian lineage representation is largely neglected in past studies partly attributable to lack of specimens; robust inclusion of samples from this region in molecular studies will help better understand the long-debated lineage diversification and origin hypotheses of this widely distributed wingless orthoptera.