Multilocus genealogies reveal multiple cryptic species and biogeographical complexity in the California turret spider Antrodiaetus riversi (Mygalomorphae, Antrodiaetidae)

Abstract

Antrodiaetus riversi (Araneae, Antrodiaetidae) is a dispersal-limited, habitat specialized mygalomorph spider species endemic to mesic woodlands of northern and central California. This species occupies a disjunct distribution, with populations in the Sierra Nevada and Coast Ranges, separated by the inhospitable Central Valley. Previous studies of morphological and allozyme variation have suggested that these populations may constitute cryptic species. We investigated the phylogeography of A. riversi using both nuclear and mitochondrial DNA sequences, collected for a comprehensive population sample. These data reveal the presence of at least five species in the A. riversi complex - these species are deeply diverged, and genealogically exclusive in both nuclear and mitochondrial genomes. Each of these species is characterized by extreme population subdivision and deep phylogeographical structuring, consistent with minimal gene flow across the dissected Californian landscape. Three species are restricted to the Coast Ranges, one to high altitudes of the central Sierran Nevada, and one species is found in both ranges. These species have allopatric distributions, although species parapatry is hypothesized to occur in several areas. Species diversification appears to have pulsed in the Late Miocene/Early Pliocene, a timing consistent with biogeographical reconstructions for many Californian taxa, and a time of turbulent geological activity in the region.

Phylogeny and DNA barcoding of inquiline oak gallwasps (Hymenoptera: Cynipidae) of the Western Palaearctic

“…While such cryptic lineages have been observed in other arthropod groups (e.g. Smith et al, 2006Smith et al, , 2007Starrett & Hedin, 2007), the Synergus complex is unusual in that its member species have a long history of taxonomic 580 and ecological study (Ross, 1951;Eady, 1952;Wiebes-Rijks, 1979;Nieves-Aldrey & PujadeVillar, 1985, 1986Pujade-Villar & Nieves-Aldrey 1990;Pujade-Villar 1992;Ronquist 1994;Schönrogge et al, 1995Schönrogge et al, , 1996aSchönrogge et al, , 1996bLiljeblad & Ronquist, 1998;Schönrogge & Crawley 2000;Pujade-Villar et al, 2003). -Villar, 1985;Pujade-Villar, 1992).…”

“…These pitfalls of relying on a single mitochondrial locus in molecular 525 barcoding are the same as those associated with its use in phylogeography, and can be avoided by using multiple unlinked nuclear loci to determine affinities between specimens (e.g. Knowles & Carstens, 2007;Starrett & Hedin, 2007). Although we have only used one nuclear locus here, the agreement in MOTU memberships between coxI and 28S D2 datasets despite the much lower levels of sequence variation in the nuclear locus (see also Rokas et al, 530 2002b;Blaxter, 2004;Ahrens et al 2007) pallipes; and (ii) the widespread phylogenetic placement and the multiple MOTU allocation 545 of specimens in the morphospecies Synergus hayneanus and S. umbraculus (Figs.…”

“…We recommend that the morphological basis of the groups of species above should be thoroughly reviewed. If reanalysis supports their maintenance as separate taxa, then species relationships should be reinvestigated using multiple nuclear locus approaches that 565 provide greater statistical power when lineage sorting is likely to be incomplete (Jenning and Edwards 2005; Knowles & Carstens, 2007;Starrett & Hedin, 2007).…”

“…While approximately 1.5 million, predominantly insect, species have been described to date (de Meeus & Renaud, 2002), these represent only a small 90 proportion of estimated global diversity and molecular studies continue to reveal cryptic taxa inseparable on the basis of morphological taxonomy (e.g. Papakostas et al, 2005;Smith et al, 2006;Bergmann & Russell, 2007;Smith et al, 2007;Starrett & Hedin, 2007), increasing the magnitude of the challenge.…”

The Genetic Variations among Populations of Tetranychus kanzawai Complex (Acari: Tetranychidae) Indicated by Using Mitochondrial, Ribosomal, and Microsatellite DNA Markers

“…For example, Starrett and Hedin (2007) found several cryptic species in the California turret spider, Antrodiaetus riversi (Mygalomorphae, Antrodiaetidae), by using both mitochondrial and nuclear DNA phylogeny, in which the sequences of the species were clearly different from each other. In the present study, although T. kanzawai and T. parakanzawai were distinct by COI haplotypes, they were monophyletic in ITS tree.…”