Zootaxa 2963: 55–68 (2011) ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ Article ZOOTAXA Copyright © 2011 · Magnolia Press ISSN 1175-5334 (online edition) A new trapdoor spider species from the southern Coast Ranges of California (Mygalomorphae, Antrodiaetidae, Aliatypus coylei, sp. nov,), including consideration of mitochondrial phylogeographic structuring MARSHAL HEDIN & DAVE CARLSON Department of Biology, San Diego State University, San Diego, CA 92182-4614, USA. E-mail: [email protected] Abstract The trapdoor spider genus Aliatypus (Araneae, Mygalomorphae, Antrodiaetidae) includes 11 described species, 10 of which are endemic to California. Aliatypus species are known from most physiographic provinces in California, with the noticeable absence of described species from the southern Coast Ranges. This paper describes a new species (Aliatypus coylei, sp. nov.) that is shown to occur at more than 20 locations, most of which are in the southern Coast Ranges. This species is morphologically most similar to members of the A. erebus species group (A. erebus Coyle and A. torridus Coyle), but males differ from those of these latter species in several features. Female specimens are more difficult to dis- tinguish from A. erebus and A. torridus, but can be easily separated using DNA characters. Collection of mitochondrial DNA sequence data from 21 sites shows that A. coylei is genetically very divergent from all described Aliatypus species, and reveals extreme population subdivision across the fragmented southern Coast Range landscape. Key words: Population subdivision, spermathecal variation, California biodiversity, mygalomorph spider Introduction Mygalomorph spiders comprise a distinct clade of the Order Araneae, and include the trapdoor spiders, tarantulas, and kin (Raven 1985, Hedin & Bond 2006). The mygalomorph spider fauna of California is one of the richest in the northern hemisphere, with the highest familial, generic, and species-diversity in the United States. Members of the families Antrodiaetidae (Coyle 1968, 1971, 1974; Coyle & Icenogle 1994; Ramirez & Chi 2004; Starrett & Hedin 2007) and Cyrtaucheniidae (Bond et al. 2001; Bond & Opell 2002; Stockman & Bond 2007; Bond & Stockman 2008) comprise the great bulk of this species diversity, and both families include genera that have radiated exten- sively and almost exclusively in California. An example is the antrodiaetid genus Aliatypus, which includes eleven described species, ten of which are endemic to California. Aliatypus are stocky, medium-sized (6–20 mm) ground- dwelling spiders that cover their burrows with a thin, flap-like trapdoor (Fig. 1A, B). Most species in the genus occur in chaparral or mid-elevation forest habitats, although some species are also found in redwood forest or high- elevation pine forests (Coyle 1974, Coyle & Icenogle 1994). When Coyle (1974) revised Aliatypus, he studied material from most physiographic provinces in California, but had few specimens available from the southern Coast Ranges. These ranges include a relatively low-lying set of north to south trending uplands, occupying a region from the San Francisco Bay south to the confluence with the Transverse Ranges at the southern terminus of the Central Valley (Fig. 1C; Schoenherr 1992). The southern Coast Ranges are bounded on the east by the Central Valley, and extend from here westward to the coast. The present-day highlands are potentially young (~0.4 Ma, Page et al. 1998), and the region is still very geologically active, as it is bisected by the San Andreas fault. Older Pliocene seaways also once fragmented the region (Hall 2002; Bowersox 2005). Modern upland habitats are characterized by standard California Floristic Province vegetation, including chaparral, oak woodlands, and limited conifer woodlands. Higher western ranges (e.g., Santa Lucia Range) create a severe rain shadow and correspondingly steep environmental gradient, with desert-like eastern habitats (along the southwestern edge of the Central Valley) much drier than coastal habitats. Many endemic taxa have evolved in this Accepted by R. Raven: 22 Jun. 2011; published: 12 Jul. 2011 55 region, including species of vertebrates (e.g., Jockusch et al. 2001; Davis et al. 2008; Parham & Papenfuss 2009), plants (Stebbins & Major 1965; Kraft et al. 2010), and arthropods (e.g., Platnick & Ubick 2001; Ubick & Briggs 2008; Bond & Stockman 2008). Coyle (1974) did not include definitive species records of Aliatypus from the southern Coast Ranges, but instead included three records simply labeled as “unidentifiable Aliatypus” (map 1 & 4, Coyle 1974). Although not explicitly discussed, it is presumed that these records represent immature specimens, or locations with small num- bers of female specimens only. Coyle (1974) did not provide collecting locality information for these specimens, and we have not examined this material. Based on on-going fieldwork conducted over the past 5–10 years, a mod- erate sample of fresh Aliatypus specimens from the southern Coast Ranges (and adjacent areas) has been accumu- lated. Most of these specimens represent a distinctive and previously undescribed species of Aliatypus, which we herein describe. We have also collected mitochondrial DNA sequence data from specimens representing most known records of this new species (21 geographic sites represented). These phylogeographic data reveal extreme mitochondrial population genetic structuring and high genetic divergences in the southern Coast Ranges. The phy- logenetic placement of this new species is briefly considered here, but is treated more comprehensively in a sepa- rate paper (Satler et al. in review). Methods We searched appropriate microhabitats for spider burrows, and extracted spiders from burrows using entrenching shovels and smaller specialized digging tools. From any particular location we attempted to collect adult spiders (almost always females), but sometimes collected only immature spiders, or collected a mixture of adult and imma- ture spiders. Immature spiders were provisionally identified to species based on association with identifiable adult specimens from the same location, or molecular clade association. Most spiders were transported live to the lab. For adults, 1–2 legs were removed from freshly-killed specimens and preserved for DNA analysis in 100% EtOH at minus 80° C; voucher specimens were stored separately in 80% EtOH at minus 20° C. Immature spiders were preserved as entire specimens in 100% EtOH at minus 80° C. All specimens were assigned a unique specimen identification number (MY number; see Table 1). Type specimens have been deposited at the California Academy of Sciences (CAS), San Francisco, California. Upon completion of our on-going studies, additional voucher speci- mens will be deposited at the CAS. Geographic location data was taken in the field using a global positioning sys- tem (GPS) device, and later verified/adjusted using Google Earth. A Google Earth kmz file of sampling sites is available as a Supplementary File. Specimens were imaged using a Visionary Digital BK plus system (http://www.visionarydigital.com), includ- ing a Canon 40D digital camera, Infinity Optics Long Distance Microscope, P-51 camera controller, and FX2 light- ing system. Individual images were combined into a composite image using Helicon Focus V5.1 software (http:// www.heliconsoft.com/heliconfocus.html), which was then edited using Adobe Photoshop CS3. Seminal recepta- cles (= spermathecae) were dissected from adult female specimens using fine forceps, immersed for 2–5 minutes in BioQuip specimen clearing fluid (www.bioquip.com) on a depression slide, then imaged directly in this fluid on slides. Other images were taken with specimens immersed in filtered 70% EtOH, using KY jelly or fine sand to secure specimens. All digital images have been deposited at Morphbank (www.morphbank.net; see Table 1). Specimen measurements were taken from digital images using a calibrated ruler tool in Photoshop CS3. All appendage measurements were recorded from the left appendage, unless otherwise indicated. Measurements mir- rored those of Coyle (1974), and only brief character descriptions are provided here. The reader is referred to Coyle (1974, figs 2–7) for more thorough character definitions: CL, CW—carapace length and width, PCL—length of pars cephalica; IFL, ITL, IML, ITarL—lengths of leg I segments (except for patella), viewed retrolaterally; IVFL, IVTL, IVML, IVTarL—lengths of leg IV segments (except for patella), viewed retrolaterally; PFL, PPL, PTL— lengths of male pedipalp segments, viewed retrolaterally; PTT—maximum depth of male pedipalp; PTX—length of male pedipalp at maximum depth; PED—distance of base of embolus to tip of conductor; PCA—distance from PED line to edge of outer conductor sclerite; SL, SW—sternum length and width; PSS—minimum distance between posterior sigilla; PSL—maximum diameter of right posterior sigilla. All measurements are reported in millimeters (mm). 56 · Zootaxa 2963 © 2011 Magnolia Press HEDIN & CARLSON NEW CALIFORNIA ALIATYPUS Zootaxa 2963 © 2011 Magnolia Press · 57 58 · Zootaxa 2963 © 2011 Magnolia Press HEDIN & CARLSON NEW CALIFORNIA ALIATYPUS Zootaxa 2963 © 2011 Magnolia Press · 59 Genomic DNA was extracted from leg tissue using a DNAeasy kit (Qiagen). The polymerase chain reaction was used to amplify a fragment of the COI mitochondrial gene, using the C1-J-1751RIV (5'-GAGTTCCTGATA- TRGCTTTTCC-3') and C1-N-2776S (5'-GGATAATCAGAATANCGNCGAGG-3') primers reported in Starrett and Hedin (2007).