TERM OF USE This pdf is provided by Magnolia Press for private/research use. Commercial sale or deposition in a public library or website site is prohibited. Zootaxa 1814: 1–20 (2008) ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ ZOOTAXA Copyright © 2008 · Magnolia Press ISSN 1175-5334 (online edition) On the spider genus Weintrauboa (Araneae, Pimoidae), with a description of a new species from China and comments on its phylogenetic relationships GUSTAVO HORMIGA Department of Biological Sciences, The George Washington University, Washington, D.C. 20052, USA. E-mail: [email protected] Abstract Weintrauboa yele new species (Pimoidae) is described and illustrated based on specimens collected in China. The taxo- nomic status and distribution of Weintrauboa insularis (Saito, 1935) new combination and of W. chikunii (Oi, 1979) are discussed and the former species is illustrated based on specimens from the Sakhalin islands. Parsimony analysis of mor- phological characters provides support for the monophyly of Weintrauboa and for its sister group relationship to the genus Putaoa Hormiga and Tu, 2008. Some comments on the phylogenetic placement of the recently erected family “Sinopimoidae” are provided. Key words: Phylogeny, Taxonomy, Morphology, Araneoidea, Linyphiidae Introduction The spider family Pimoidae comprises four genera and thirty one extant species (Platnick, 2008; Hormiga & Tu, 2008). Pimoids are known from Western North America (14 species in two genera, from California through Alaska), Southern Europe (two species in one genus, from Spain, France and Italy) and Asia (15 spe- cies in three genera, from the Himalayas area, China, Japan and the Sakhalin islands). Several species of pimoids from China (Griswold and Hormiga, unpublished) and California (Hormiga and Lew, unpublished) remain to be described. The diversity and distribution of pimoids suggests that this family is a relictual group which had a broader Holarctic distribution in the past (Hormiga, 1994a, 2003; Wang et al. 2008). So far six fossil species of pimoids, all of them in the genus Pimoa, have been described from Baltic amber (Wunder- lich, 2004). The genus Weintrauboa was originally described to include two species from Japan and the Sakhalin islands (Hormiga, 2003): W. contortipes (Karsch, 1881), the type species, and W. chikunii (Oi, 1979). A new species from the Yunnan province of China was recently added by Yang, Zhu and Song (2006). More recently, Xu and Li (2007) have described another new species from China, W. megacanthus and have reported the occurrence of W. chikunii in the Chinese province of Sichuan. Hormiga and Tu (2008) transferred megacan- thus to a new genus, Putaoa, which also includes a second Chinese species, P. huaping Hormiga and Tu, 2008 (the type species). On the other hand, Weintrauboa chikunii had been previously known to occur in Japan and the Sakhalin islands (Hormiga, 2003) and therefore the Chinese records reported by Xu and Li (2007) would represent a significant extension of the distribution range of this species (Sichuan is more than 3,000 km away from the type locality of W. chikunii in Japan; see map in Fig. 10). Examination of the Chinese specimens described by Xu and Li (2007) suggests that they are not conspecific with W. chikunii and that they belong to a new species. In this paper I describe this new species of Weintrauboa from China and, in light of newly stud- ied specimens the Sakhalin islands, I clarify the status of the species of Weintrauboa in Japan and adjacent islands. Accepted by N. Scharff: 26 May 2008; published: 2 Jul. 2008 1 TERM OF USE This pdf is provided by Magnolia Press for private/research use. Commercial sale or deposition in a public library or website site is prohibited. Material and methods Morphological methods are described in detail in Hormiga (2000, 2002). Taxonomic descriptions follow the format of Hormiga (1994a, 2002). Specimens were examined and illustrated using a Leica MZ16A and a Leica MZAPO stereoscopic microscope, with a camera lucida. Further details were studied using a Leica DMRM compound microscope with a drawing tube or an Olympus BX40 compound microscope. Digital images were taken with a Leica DFC 500 camera. The digital images depicting the habitus and genital mor- phology are a composite of multiple images taken at different focal lengths along the Z axis and assembled using the software package Leica Application Suite. Left structures (e.g., palps, legs, etc.) are depicted unless otherwise stated. Most hairs and macrosetae are usually not depicted in the final palp and epigynum drawings. All morphological measurements are in millimeters. Somatic morphology measurements were taken using a scale reticle in the dissecting microscope. The position of the metatarsal trichobothrium is expressed as in Denis (1949). Female genitalia were excised using surgical blades or sharpened needles. Epigyna and palps were transferred to methyl salicylate (Holm, 1979) for examination under the microscope, temporarily mounted as described in Grandjean (1949) and Coddington (1983). Anatomical abbreviations used in the text and figures Male Palp C conductor CP cymbial process E embolus PEP pimoid embolic process Epigynum CD copulatory duct FD fertilization duct S spermatheca Somatic morphology ALE anterior lateral eye(s) AME anterior median eye(s) PLE posterior lateral eye(s) PME posterior median eye(s) Cladistic analysis Taxa. I have added the new species (Weintrauboa yele) to the character matrix of Hormiga and Tu (2008), which included three other Weintrauboa species, the two known species of the recently described genus Putaoa, four species of Pimoa, Nanoa enana Hormiga, Buckle and Scharff, 2005 and 21 linyphiid species. The species coded under Weintrauboa chikunii in the matrix of Hormiga and Tu (2008) is actually W. insularis (Saito, 1935) n. comb., as it is discussed in the taxonomic section of the present paper. Due to the lack of female specimens of this latter species many character were not coded in the previous matrix but are coded for insularis in the present one. I have also scored representatives of three other araneoid families (Tetrag- nathidae, Theridiosomatidae, and Theridiidae) to root the “linyphioids.” The Linyphiidae sample attempts to represent morphological diversity at the subfamilial level. The goal of this analysis is to study the placement of the new Weintrauboa species within Pimoidae. The matrix includes a total of 35 taxa (Appendix 2). Characters. The characters used in the current analysis are those of Hormiga and Tu (2008) with one additional character (character 3, see Appendix 1). Six of the 83 characters in the matrix are parsimony unin- formative but are kept because they may be useful with a different taxonomic sample. 2 · Zootaxa 1814 © 2008 Magnolia Press HORMIGA TERM OF USE This pdf is provided by Magnolia Press for private/research use. Commercial sale or deposition in a public library or website site is prohibited. Analyses. The character matrix was edited and managed using the program Mesquite version 2.0 (Maddi- son & Maddison 2007). The parsimony analyses were performed using the computer program TNT version 1.1 (Goloboff et al. 2007) using both equal weights and implied weights (Goloboff 1993). Mesquite version 2.0 and WinClada version 1.00.08 (Nixon 1999) were used to study character optimizations on the cla- dograms. Ambiguous character optimizations were resolved so as to favor reversal or secondary loss over convergence (Farris optimization or ACCTRAN). The 18 multistate characters in the matrix were treated as non-additive (unordered or Fitch minimum mutation model; Fitch 1971). Bremer support indices (Bremer 1988, 1994) were calculated in TNT using the macro “bremer.run.” Parsimony jackknife indices (Farris et al. 1996) were also calculated in TNT using 10,000 replicates (traditional search with TBR), a 0.36 removal probability and collapsing groups with a frequency below 50% (both clade support indices are reported in Fig. 11). Results Heuristic searches in TNT under equal weights, collapsing branches if supported ambiguously (“Rule 1”) and performing 1000 replicates of TBR resulted in four minimal length trees of 212 steps in all 1000 replicates (with ensemble consistency and retention indices of 0.50 and 0.75, respectively; the consistency index is 0.48 after exclusion of the six uninformative characters). Two nodes are collapsed in the strict consensus cla- dogram, both within Linyphiidae (Fig. 11). Implied weights analyses in TNT under k = 1 and 3 resulted in the same cladogram for the internal relationships of Pimoidae (that is, identical to that found under equal weights) with tree lengths under equal weights of 219 and 212 steps, respectively. Consequently k values higher than 3 converge on the same pimoid internal relationships (e.g., k values of 6, 12 and 50 result in optimal topologies that are 212 steps under equal weights). The genus Weintrauboa is monophyletic and sister to Putaoa. Wein- trauboa contortipes (Karsch, 1881) is sister to a clade that includes the remaining species in the genus. Discussion Although the discovery of a new species of Weintrauboa in China, as well as the availability of new speci- mens of W. insularis n. comb., has improved our understanding of this interesting lineage of pimoids, the group remains poorly studied. Most species are known after only a few museum specimens (none seem to be available for study in the case of the Japanese species W. chikunii) and consequently the distribution ranges of the five described species (see map in Fig. 10) should be considered very preliminary. The limited species dis- tribution data available suggest that additional species probably exist in China, given that there is a distribu- tional gap more than 2,500 km. wide between the records of W. yunnan (in Yunnan, China) and the most western records of W. contortipes (in Honshu, Japan). We do not know much about their biology either, if any- thing. The sheet web of W.