2007. The Journal of Arachnology 35:205-207 SHORT COMMUNICATION ON A NEW SPECIES GROUP IN THE SPIDER GENUS SOCALCHEMMIS (ARANEAE, TENGELLIDAE) Norman I. Platnick: American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024 USA. E-mail: [email protected] Darrell Ubick: California Academy of Sciences, 875 Howard Street, San Francisco, California 94103 USA ABSTRACT. A new species, Socalchemmis arroyoseco, described from Monterey County, California, is clearly not a member ofeither ofthe species groups currently recognized in that genus, but does appear to be more closely related to those species groups than to the other genera in the Liocranoides complex. Keywords! Taxonomy, North America, Liocranoides, Anachemmis, Titiotus, California North America is home to a distinctive group of all four genera has been conducted, and it isn’t ob- large hunting spiders with a remarkable character vious that enough morphological characters are combination: the presence ofthree tarsal claws and available to answer the question robustly. However, claw tufts (tufts are usually found only in two- multiple features of the male palp suggest that the clawed taxa). This highly unusual combination of new species is more closely related to Socalchem- features has historically created difficulties both in mis than to the other three genera. The presence of the identification and phylogenetic placement of an apical retrolateral tibial apophysis accompanied these taxa (Platnick 1999; Platnick & Ubick 2001, by a subapical, more dorsally situated apophysis 2005). Four genera are currently recognized in this suggests that the new species is closer to Liocra- complex: Liocranoides Keyserling 1881 (in the noides and Socalchemmis than to Anachemmis eastern USA); and Titiotus Simon 1897, Anachem- (males ofwhich have only a tiny dorsal apophysis) mis Chamberlin 1919, and Socalchemmis Platnick or Titiotus (males of which have multiple apophy- & Ubick 2001 (in California and adjacent states). ses, in a rather different conformation). In addition, We report here on a remarkable new species re- both the embolus and the median apophysis are cently collected in Monterey County, California, long and narrow (quite unlike the shorter and wider that clearly belongs to this complex but is not ob- structures typical of Liocranoides, Anachemmis, viously a member of any of these four genera. It and Titiotus). differs from the eastern species ofLiocranoides in Thus, we conclude that the new species is prob- having anelongated median apophysis inmales and ably closest to Socalchemmis. Two species groups lacking anelevatedepigynalhoodinfemales. Itdif- of Socalchemmis are currently recognized, but it is fers from the western genera as well. Males differ clearthatthe new species cannotbeplaced ineither from those of Titiotus in having only two tibial ofthose groups. Pending the discovery ofaddition- apophyses, fromthoseofAnachemmisinhavingthe al taxa and a detailed cladistic analysis (hopefully more dorsal tibial apophysis of males large and including molecular data), we suggest that the new well-developed, and from those ofSocalchemmisin species probably represents the sister group of So- lacking aprolateral extension atthe base ofthe pal- calchemmis, as currently constituted. Given theten- pal embolus that results in abipartite appearance of tative nature of this conclusion, it seems better to the embolus. Females differ from those ofall three expand the concept of Socalchemmis, at least tem- western genera in lacking a median epigynal sep- porarily, by including the new species as a third tum. species group, rather than to create a new generic The question, then, is what the closest relatives name that might prove, on further analysis, to be of the new species might be. No formal cladistic superfluous. analysis ofgeneric level relationships incorporating The new species is an outlier geographically, as 205 206 THE JOURNAL OF ARACHNOLOGY — Figures 1-5. Socalchemmis arroyoseco new species: 1. Left male palp, prolateral view; 2. Left male palp, ventral view; 3. Left male palp, retroiateral view; 4. Epigynum, ventral view; 5. Epigynum, dorsal view. well; most Socalchemmis species occur in southern Family Tengellidae Dahl 1908 California and adjacent parts of Arizona and Baja Genus Socalchemmis Platnick & Ubick 2001 California Norte. The new species is from the same Type species.—Anachemmis doUchopus Cham- area in Monterey County, California that is inhab- berlin 1919 by original designation. ited by the most northern of the previously known species, 5*. monterey Platnick and Ubick 2001. Socalchemmis arroyoseco new species Specimens are deposited in the CaliforniaAcademy Fig—s. 1-5 ofSciences, San Francisco (CAS) andtheAmerican Material examined. Holotype male and allo- Museum of Natural History, New York (AMNH). type female taken in pitfall traps in an oak forest at — PLATNICK & UBICK—NEW SOCALCHEMMIS GROUP 207 an elevation of 1,126 ft [= 343 m] at Arroyo Seco, dO-0-0; III rO-1-1; metatarsi: I, II pO-0-0, rO-0-0; IV Indians Road, 36°13.8'N, 121°29.5'W, Monterey pO-1-2, v3-3-lp. Epigynum without medium sep- jl County, California, USA, 18 June-24 October tum, with short lateral margins, distinct anterolat- 2004, D. & S. Ubick (CAS). eral margins, and arched anterior margin (Figs. 4, Other material examined: USA: California: 5). — MSoSnWterAeryroCyoounSteyc:o 1Ca$m,pgInrdoiuannds,Ro7adM,ayca.19195ai,rokamk edNaattutrhraelehsiistteos,ryt,woThailsonsgpeIcnideisanhsasRboeaednaconldletchte- forest, elev. 1,100 ft [= 335 m], D. Ubick, W. Sa- thirdjustsouth ofArroyo SecoCampground, which vary (AMNH); 2 S, Arroyo Seco, Indians Road, enclose an area of only about 1 km in diameter. 36°13.8'N, 121°29.5'W, 11 June-28 November Although these sites are near the Hastings field sta- 2003, pitfalls, oak forest, elev. 1126 ft [= 343 m], tion, extensive collecting there overseveraldecades D. & S. Ubick (AMNH); 1 6, same data, 18 June- has produced no Socalchemmis specimens. All 24 October 2004, D. & S. Ubick (CAS); 2 6, Ar- three ofthe inhabited sites are densely forested,pri- royo Seco, The Lakes, 36°13.9'N, 12r29.rw, 19 marily by oaks, but are adjacent to open canopy, August-11 November 2001, pitfalls, base of talus formed by chaparral at Indians Road and an exten- slope in oak-bay forest, elev. ca. 1000 ft [= 305 ssipveecitamleuns csollolpeectaetdthbeychaamnpdgrwoausndonsitteh.eTuhnedesrisnugrl-e m],EtDy.moSlloSg.yU.b—icTkhe(CsApeSc)i.fic name is a noun in ap- Tfahcee sopfeacibmoeunlsdefrrodmeeppiltyfalilmtbreadpdsesdugignesptoraoussursfoaicle. position taken—from the type locality. activity in summer to autumn, whereas the hand- Diagnosis. The sinuous, dentate embolus of collected female—was taken in early May. males (Fig. 2), and the arched anterior epigynal Distribution. Known only from the vicinity of margin offemales (Fig. 4), are diagnostic. Arroyo Seco in Monterey County, California. Description. Male: Total length 4.5 mm. Car- LITERATURE CITED apace paleyellow, darkestanteriorly; abdomenpale gray, unpatterned; femora yellow, more distal leg Platnick, N.I. 1999. A revision of the Appalachian segments grading to light brown on metatarsi and spider genus Liocranoides (Araneae; Tengelli- toarras:i.ILpeO-g1-s1p;inIaItpiOo-n2-t1y;piIcIaIlrf2o-rl-gl;enIuVsreOxc-eMp;t:mfeetma-- PlaNdtanoeir)ct.kh,ANmA.emIre.ir&ciacnaDn.MUusbpsiiedcekur.ms2No0of0v1it.thaeAtensreew3vi2s8gi5eo:nn1u-os1f3St.oh-e tarsi: I pO-1-0, rO-1-0; II pi-1-0, rO-1-0. Embolus calchemmis (Araneae, Tengellidae), American relatively long, twisted at about half its length, Museum Novitates 3339:1-25. bearing distally directed denticle; dorsal tibial Platnick, N.I. & D. Ubick. 2005. A revision ofthe apophysis directed laterally, smaller than ventral North American spider genus Anachemmis apophysis (Figs. 1-3). Chamberlin (Araneae, Tengellidae). American Female: Total length 4.9 mm. Coloration as in Museum Novitates 3477:1-20. male. Leg spination typical for genus except: fem- ora: I pO-Ll, rO-1-1; II pO-2-1, rl-1-1; III rO-2-1; Manuscript received3 May 2006, revised 1 August IV rO-0-1; tibiae: I dO-0-0, pO-0-0, rO-0-0; II 2006.