Spider of North America

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1 Spider of North America 69 Chapter 29 GNAPHOSIDAE 24 genera, 255 species by Darrell Ubick Common name Ground spiders; mouse spider [Scotophaeus blackwallii (THORELL 1871a)]. Similar families Prodidomidae p. xxx, Corinnidae (Phrurolithinae) p. xxx. Diagnosis Gnaphosids may be distinguished from other 2-clawed entelegyne spiders, except prodidomids, by their enlarged and separated ALS, concave endites, and modified PME (flattened, oval, to irregular), and from prodidomids by having cylindrical (rather than flattened) ALS with relatively fewer and shorter spigots, PER straight to moderately procurved (strongly procurved in Scopoides and prodidomids), and pectinate tarsal claws (smooth in most prodidomids). Characters body size: 2-17 mm. color: usually brown to gray to black, abdomen sometimes with chevrons or white bands or stripes. carapace: pyriform, low, with distinct fovea. sternum: with precoxal triangles (except Talanites). eyes: eight in two straight rows, PER rarely procurved; PME modified, oval to irregular in shape and flat. chelicerae: usually not geniculate, margins with teeth, keels, lobes or carinae, rarely smooth. mouthparts: endite with oblique medial depression, with serrula. legs: prograde, moderately to lightly spined; tarsi with two pectinate claws, claw tufts, and often scopulae; posterior metatarsi of some genera with preening combs or brushes. abdomen: elongate and somewhat flattened; often with scute in male. spinnerets: ALS cylindrical and widely separated at base, composed of one segment, and with enlarged spigots. respiratory system: with one pair of booklungs and with single tracheal spiracle near spinnerets. genitalia: entelegyne; female epigynum at least moderately sclerotized, variable in structure; male palp with RTA, usually a simple prong, bulb with embolus, conductor, and usually with median apophysis. Distribution Although most Nearctic gnaphosid genera are widely distributed, the majority of the species is concentrated in the western and southwestern regions. Orodrassus, Parasyrisca, and most Gnaphosa are primarily or exclusively northern and western, whereas Synaphosus, Eilica, Camillina, and Gertschosa are southern. Litopyllus is restricted to the eastern half of the area and Scopoides to the southwest. Natural history Gnaphosids are primarily ground dwellers, only rarely found in arboreal habitats, and may be the most abundant spiders in drier and more open biomes (Dippenaar-Schoeman & Jocqué 1997). They are predominantly nocturnal Fig Herpyllus ecclesiasticus HENTZ 1832 and cryptozoic and are found in leaf litter, beneath rocks, and within and under decomposing wood. Synanthropic species, such as Scotophaeus blackwalli and Urozelotes rusticus (L. KOCH 1872b), occur in and around buildings. Being wandering hunters, gnaphosids use silk minimally, only for draglines, retreats, and eggsacs. The eggsacs may be constructed within a retreat and guarded by the female, or secured to the substrate and either guarded or abandoned. The eggsacs of at least some species are flat with a swollen center, like a fried egg, and made of a parchment-like silk. Gnaphosids are mostly generalized predators, utilizing a wide variety of prey, including other spiders. Species of Micaria and Callilepis have been observed to prey on ants (Heller 1976, Sauer & Wunderlich 1991). Ant association is more extreme in Micaria, which are convincing ant mimics and, unlike most gnaphosids, are diurnally active and occur in the company of various ant species (Platnick & Shadab 1988).

2 70 Taxonomic history and notes As Gnaphosidae is defined by conspicuous derived characters, most Nearctic members have been traditionally clearly placed in the family. One exception is Micaria that, because of its ant mimicry and reduced and only moderately separated ALS, has previously been associated with the clubionoid myrmecomorphs - the castianeirines and phrurolithines - but recently clearly placed in Gnaphosidae (Wunderlich 1979, Platnick & Shadab 1988). Also ambiguous has been the placement of the prodidomines which, based on the presence of morphologically intermediate taxa, were synonymized with the Gnaphosidae by Platnick & Shadab (1976c). After detailed study of spinneret morphology, the prodidomids have been restored to family status (Platnick 1990). Interestingly, the gnaphosid subfamily Echeminae, represented here by Scopoides, shares some prodidomid characters: the procurved PER and anteriorly displaced ALS. Most of the pioneering work on Nearctic gnaphosid taxonomy was by Chamberlin, who generated scores of poorly defined taxa. The entire fauna has been recently revised in a long series of papers by Platnick and collaborators and the genera have been clustered into provisional subfamilies, of which the Drassodinae were regarded as basal and probably not monophyletic (Platnick 1990). Genera DRASSODINAE Drassodes WESTRING 1851, Haplodrassus CHAMBERLIN 1922, Orodrassus CHAMBERLIN 1922, Parasyrisca SCHENKEL 1963, Sosticus CHAMBERLIN 1922, Synaphosus PLATNICK & SHADAB 1980a, Talanites SIMON 1893a LARONIINAE Callilepis WESTRING 1874, Eilica KEYSERLING 1891 GNAPHOSINAE Gnaphosa LATREILLE 1804b ZELOTINAE Camillina BERLAND 1919b, Drassylus CHAMBERLIN 1922, Trachyzelotes LOHMANDER 1944, Urozelotes DE MELLO- LEITÃO 1938a, Zelotes GISTEL 1848 HERPYLLINAE Cesonia SIMON 1893a, Gertschosa PLATNICK & SHADAB 1981b, Herpyllus HENTZ 1832, Litopyllus CHAMBERLIN 1922, Nodocion CHAMBERLIN 1922, Scotophaeus SIMON 1893a, Sergiolus SIMON 1891c MICARIINAE Micaria WESTRING 1851 ECHEMINAE Scopoides PLATNICK 1989b Distribution summaries (* = introduced genera) Worldwide (Drassodes, Micaria, *Urozelotes, Zelotes) Holarctic (Callilepis, Gnaphosa, Haplodrassus, Parasyrisca, Talanites) Nearctic (Herpyllus, Orodrassus, Scopoides, Sosticus) North America (Cesonia, Litopyllus, Nodocion, Sergiolus) Nearctic and Neotropical (Drassyllus) Neotropical (Gertschosa) Neotropical and African (Camillina) Gondwandan to South Nearctic (Eilica) Palearctic (*Scotophaeus, *Synaphosus, *Trachyzelotes)

3 Spider of North America 71 Key to genera North America North of Mexico Body antlike (Fig. 29.2); abdomen with iridescent scales (Fig. 29.3); ALS small, often appearing only slightly separated (Fig. 29.4); genitalia, Figs Micaria Div. 41 species Dist. widespread Refs. Platnick & Shadab 1988, Body not antlike; abdomen lacking iridescent scales; ALS large, well separated (Fig. 29.7) (1) Metatarsi III and IV with ventrodistal preening comb (Fig. 29.8)... 3 Metatarsi III and IV lacking ventrodistal preening comb (2) Chelicera with cluster of stiff setae on anteromedian surface (Fig. 29.9); genitalia, Figs Trachyzelotes Div. 4 species Dist. most in w USA, also IL, FL Ref. Platnick & Murphy 1984 Note all Nearctic species have been introduced from the Mediterranean region. Chelicera without such cluster of setae (3) Genitalia as in Figs Urozelotes Div. 1 species; U. rusticus (L. KOCH 1872b) Dist. widespread in USA, ON Refs. Platnick & Murphy 1984, Platnick & Dondale 1992 Note this enigmatic species is a synanthrope with a worldwide distribution but whose origins are not known Genitalia otherwise (4) PME usually round, rarely oval, barely larger than PLE (Fig ); PE nearly equidistant; PER straight, occasionally slightly procurved; cheliceral retromargin with 1 tooth and 1 denticle; male palpus with intercalary sclerite (Fig ); epigynum Figs Zelotes Div. 47 species Dist. widespread Refs. Platnick & Shadab 1983, Platnick & Dondale 1992, Platnick & Murphy 1998, Platnick & Prentice 1999, Paquin & Dupérré 2003 PME usually oval, larger than PLE, closely spaced; PER slightly procurved (Fig ); cheliceral retromargin with 2-3 teeth; male palpus lacking intercalary sclerite (5) Male with embolus stout (Fig ); female with median epigynal plate (Fig ); known from FL and AL Camillina Div. 2 species Dist. FL, AL Refs. Platnick & Shadab 1982b Note Camillina elegans (BRYANT 1940) [Figs ] is native to Florida and the Caribbean, C. pulchra (KEYSERLING 1891) recorded from FL - TX (A. Dean, pers. comm.), is apparently introduced from Brazil Male with embolus long, whip-like (Fig ); epigynum variable, usually with paired depressions (Fig ); widespread... Drassyllus Div. 46 species Dist. widespread Refs. Platnick & Shadab 1982a, Platnick 1984, Platnick & Corey 1989, Platnick & Dondale 1992, Paquin & Dupérré

4 72 7(2) Trochanters deeply notched (Fig ); male palpus with narrow cymbium, no wider than tibia (Fig ); epigynum as in Fig Drassodes Div. 7 species Dist. widespread Refs. Platnick & Shadab 1976a, Trochanters unnotched (Fig ) or with shallow notches (Fig ); male palpus with cymbium typically much wider than tibia (7) PER strongly procurved (Fig ); sw USA; genitalia, Figs Scopoides Div. 7 species Dist. sw USA to Mexico Ref. Platnick & Shadab 1976b Note Scopodes CHAMBERLIN 1922 is the original but unavailable name PER straight or slightly recurved, rarely slightly procurved; widespread (8) Cheliceral retromargin with serrated keel (Fig ) or lobes. (Fig ) Cheliceral retromargin lacking keel or lobes (9) Cheliceral retromargin with a serrated keel (Fig ); endites usually rounded laterally (Fig ); genitalia, Figs Gnaphosa Div. 20 species Dist. widespread Refs. Platnick & Shadab 1975a, Cheliceral retromargin with rounded lobe or lobes (Fig ); endites usually angular laterally (Fig ) (10) Cheliceral retromargin with one rounded lobe (Fig ); sternum short, stout, about twice as wide as length of endites (Fig ); PME flattened, transverse (Fig ); genitalia, Figs Callilepis Div. 7 species Dist. widespread Refs. Platnick 1975a, Platnick & Dondale 1992, Paquin & Dupérré Cheliceral retromargin with 2-3 rounded lobes (Fig ); sternum narrow, elongate, about as wide as length of endites (Fig ); PME rectangular (Fig ); s USA... Eilica Div. 1 species: E. bicolor BANKS 1896e [Figs ] Dist. s CA, s TX, FL Ref. Platnick 1975b 12(9) Female epigynum with scape (Fig ) Sosticus, in part Div. 3 species, 2 key out here Dist. widespread Refs. Platnick & Shadab 1976b, Males, or female with epigynum lacking scape (12) Cheliceral retromargin with 2 or 3 teeth (Fig ) Cheliceral retromargin with at most one tooth (Figs ) (13) Tibia IV lacking dorsal spines Tibia IV with 2 dorsal spines

5 Spider of North America 73 15(14) PME separated by no more than 1/2 their diameter (Fig ); tibia I lacking ventral spines; RTA flattened and dorsally positioned (Fig ); genitalia, Figs Haplodrassus Div. 9 species Dist. widespread Refs. Platnick & Shadab 1975b, PME separated by at least their diameter (Fig ); tibia I with at least 1 ventral spine; RTA neither flattened nor dorsally positioned (15) Tibia I with 2 pairs of ventral spines; RTA with single prong (Fig )... Parasyrisca Div. 1 species: P. orites (CHAMBERLIN & GERTSCH 1940) [Figs ] Dist. BC, WA Refs. Platnick & Shadab 1975b, Ovtsharenko, Platnick, & Marusik 1995, Platnick & Dondale 1992 Note previously included in Orodrassus Tibia I with 1 ventral spine; RTA with two prongs (Fig ); genitalia, Figs Orodrassus Div. 3 species Dist. CAN, w USA Refs. Platnick & Shadab 1975b, Ovtsharenko, Platnick, & Marusik 1995, Platnick & Dondale 1992, Paquin & Dupérré (14) Male RTA longer than tibia, and median apophysis in apical position (Fig ); palp ventral view (Fig ); female epigynum with scape (Fig ) Sosticus, in part Div. 3 species, 2 key out here: S. californicus PLATNICK & SHADAB 1976b and S. insularis (BANKS 1895d) Dist. CAN, e USA Refs. Platnick & Shadab 1976b, Male RTA shorter than tibia, and median apophysis in median position (Fig ); female epigynum without scape (Fig )... Talanites Div. 5 species Dist. CAN, se USA Refs. Platnick & Shadab 1976b, Platnick & Ovtsharenko 1991, Ubick & Moody 1995 Note Rachodrassus CHAMBERLIN 1922 is a synonym (13) Abdomen with pale stripes or bands (Figs. 29.1; ; 29.69; ) Abdomen concolorous, rarely with faint chevron pattern posteriorly (some Synaphosus) (18) Cheliceral retromargin lacking denticles or teeth (Fig ); abdomen with transverse white markings (Fig ); genitalia Figs Sergiolus Div. 16 species Dist. widespread Refs. Platnick & Shadab 1981e, Paquin & Dupérré 2003 Note species were previously included in the Palearctic genus, Poecilochroa WESTRING 1974 Cheliceral retromargin with one denticle (Fig ); abdominal markings variable (19) Abdomen with transverse white markings anteriorly (Fig ); s TX... Gertschosa Div. 1 species: G. amphiloga (CHAMBERLIN 1936b) [Fig ] Dist. s TX Ref. Platnick & Shadab 1981b Note the male is not known Abdomen with longitudinal white markings (Figs. 29.1; ); widespread

6 74 21(20) Abdomen with single median white stripe; carapace dark, concolorous (Fig. 29.1); PE equidistant Herpyllus, in part Div. 13 species, 2 key out here: H. ecclesiasticus HENTZ 1832 [Fig. 29.1] and H. propinquus (KEYSERLING 1887b) Dist. widespread Refs. Platnick & Shadab 1977, Abdomen with two or more white stripes (Fig ); carapace usually with white markings; PME closer to PLE than to each other; genitalia, Figs Cesonia Div. 10 species Dist. widespread Refs. Platnick & Shadab 1980b, (18) Trochanters not notched (Fig ) At least posterior trochanters slightly notched (Fig ) (22) Male palpus with embolus fully exposed and RTA bifid (Fig ); female epigynum with a scape (Fig ) Sosticus, in part Div. 3 species, 1 keys out here: S. loricatus (L. KOCH 1866c) [Figs ; 29.76] Dist. se CAN + ne USA to Rocky Mountains Refs. Platnick & Shadab 1976b, Note Sostogeus CHAMBERLIN & GERTSCH 1940 is a synonym Male palpus with embolus partially enclosed in folded median apophysis and RTA single (Figs ); female with epigynum lacking a scape (Figs )... Synaphosus Div. 2 species: S. paludis (CHAMBERLIN & GERTSCH 1940) [Figs ; 29.79] and S. syntheticus (CHAMBERLIN 1924b) [Figs ; 29.80] Dist. s USA to MEX Refs. Platnick & Shadab 1980a, Ovtsharenko, Levy, & Platnick 1994 Note This genus is native to the Palearctic region. Ovtsharenko et al mention that S. paludis is not congeneric and represents an undescribed genus (22) Cheliceral promargin toothed (Fig ); tibia IV with one dorsal spine; PME subequal to PLE, separated by their diameter Cheliceral promargin with carina (Fig ); tibia IV lacking dorsal spine; PME larger than PLE, usually separated by less than a diameter (24) Male palpus with embolus bearing enlarged base, median apophysis elongate, inconspicuous (Fig ); female with spermatheca lacking terminal bulbs (Fig ) Herpyllus, in part Div. 13 species, 11 key out here Dist. widespread Refs. Platnick & Shadab 1977, Platnick & Dondale 1992 Male palpus with embolus sinuous, lacking enlarged base, median apophysis hooked (Fig ); female with spermatheca bearing terminal bulbs (Fig ) Scotophaeus Div. 1 species: S. blackwalli (THORELL 1871a) Dist. w coast from CAN to MEX, Gulf states Refs. Platnick & Shadab 1977, Platnick & Dondale 1992 Note the genus is native to the Palearctic region and this species is a cosmopolitan synanthrope (24) Cheliceral retromargin with single tooth (Fig ); PER procurved; male palpus with cymbium not excavated (Fig ); female with spermatheca clearly bipartite (Fig )... Litopyllus Div. 2 species Dist. e USA Refs. Platnick & Shadab 1980a, Platnick & Dondale 1992 Cheliceral retromargin lacking teeth (Fig ); PER straight; male palpus with cymbium excavated to receive RTA (Fig ); female with spermathecae not conspicuously bipartite (Fig )... Nodocion Div. 6 species Dist. widespread Refs. Platnick & Shadab 1980a, Platnick & Dondale