Aptostichus cajalco, Bond, Jason E., 2012

Bond, Jason E., 2012, Phylogenetic treatment and taxonomic revision of the trapdoor spider genus Aptostichus Simon (Araneae, Mygalomorphae, Euctenizidae), ZooKeys 252, pp. 1-209 : 148-151

Aptostichus cajalco sp. n. Figures 323-331Map 33

Types.

Male holotype and female paratype (MY3778) from California, Riverside County, 2.9km along Cajalco Road, west of Lake Matthews, 33.8256, -117.4957 1, 265m, coll. 6.ix.1999 W. Icenogle; additional male paratypes (AP1239, 1236) from the type locality coll. W. Icenogle 9.ix.1999, 6.x.1999; deposited in AUMNH.

Etymology.

The specific epithet is a noun in apposition taken from the type locality, Cajalco Canyon.

Diagnosis.

Male and female Aptostichus cajalco can be diagnosed from all other Simus group species by having a round sternum that is approximately as wide as it is long; all other species have a sternum that is more typical (widest at coxae III-IV junction).

Description of male holotype.

Specimen preparation and condition. Specimen collected from pitfall trap, preserved in 80% EtOH. Coloration in good condition. Pedipalp, leg I left side removed, stored in vial with specimen. General coloration. Carapace, chelicerae, legs yellowish red 5YR 4/6. Abdomen uniform brown 7.5YR 4/3, distinct dorsal mottled chevron markings (Fig. 323). Cephalothorax. Carapace 3.66 long, 3.04 wide, glabrous, stout black bristles along fringe; surface smooth, pars cephalica elevated. Fringe, posterior margin with black bristles. Foveal groove deep, strongly recurved. Eyes on low mound. AER slightly procurved, PER slightly recurved. PME, AME subequal diameter. Sternum moderately setose, appears round in shape, STRl 2.02, STRw 1.82. Posterior sternal sigilla small, positioned away from margin but not in center, not contiguous, anterior sigilla pairs small, oval, marginal. Chelicerae with distinct anterior tooth row comprising 4 teeth, posterior margin with single row of small denticles. Palpal endites, labium, lacks cuspules, LBw 0.60, LBl 0.29. Rastellum consists of ~8 stout spines not on prominent mound. Abdomen. Setose, heavy black setae intermingled with fine black setae. Legs. Leg I: 3.88, 3.20, 2.39, 1.68, 1.20; leg IV: 3.68, 2.20. Very light to no tarsal scopulae on legs I, II. Tarsus I with single, slightly staggered row of 11 trichobothria. Leg I spination pattern illustrated in Figures 324, 325, 327; TSp 8, TSr 5, TSrd 0; distinct short spines on ventral surface tarsus I. Pedipalp. Palpal tibia short, width more than half-length, with distinct patch of medial/distal retrolateral spines (Fig. 326). Palpal bulb short; embolus stout, dorsal-ventrally flattened with slight curvature at its midpoint, serrated distally. PTw 0.68, PTl 1.34, Bl 0.60.

Variation (5). Cl 3.63-4.08, 3.87 ± 0.09; Cw 3.01-3.48, 3.20 ± 0.1; STRl 1.98-2.25, 2.14 ± 0.06; STRw 1.74-2.03, 1.91 ± 0.06; LBw 0.60-0.68, 0.62 ± 0.02; LBl 0.34-0.39, 0.36 ± 0.01; leg I: 3.72-4.10, 3.87 ± 0.06; 3.08-3.26, 3.15 ± 0.03; 2.26-2.48, 2.36 ± 0.04; 1.56-1.70, 1.63 ± 0.03; 1.10-1.20, 1.15 ± 0.02; leg IV: 3.57-4, 3.75 ± 0.09; 2.08-2.29, 2.18 ± 0.03; PTl 1.28-1.39, 1.31 ± 0.02; PTw 0.66-0.75, 0.71 ± 0.02; Bl 0.60-0.71, 0.66 ± 0.02; TSp 8-11, 9.80 ± 0.73; TSr 3-7, 5.20 ± 0.8; TSrd 0-0, 0 ± 0.

Description of female paratype.

Specimen preparation and condition. Female collected from pitfall trap, prepared in same manner as male holotype. Genital plate, removed, cleared in trypsin, stored in microvial with specimen. General coloration. Carapace, legs, chelicerae, strong brown, 7.5YR 4/6. Abdomen brown, 7.5YR 5/3 with distinct mottled striping (Fig. 328). Cephalothorax. Carapace 4.00 long, 3.44 wide, generally glabrous, very sparse fine black setae; generally smooth surface, pars cephalica moderately elevated. Fringe lacks setae. Foveal groove deep, straight. Eye group slightly elevated on low mound. AER slightly procurved, PER slightly recurved. PME-AME subequal diameter. Sternum round in appearance, moderately setose, STRl 2.10, STRw 1.93. Three pairs of sternal sigilla anterior pairs small in size, oval, marginal; posterior pair moderate in size, elongate, mesially positioned but not contiguous. Chelicerae anterior tooth row comprising 4 teeth with posterior margin denticle patch. Palpal endites with 24 cuspules concentrated at inner (promargin) posterior heel; labium lacks cuspules, LBw 0.68, LBl 0.43. Rastellum consists of 12 stout spines not positioned on mound; fringe of short spines along distal promargin extending upward from rastellum. Abdomen. Moderately setose. PLS all 3 segments with spigots. Terminal segment 1/2 length of medial segment, 2 enlarged spigots visible at tip. PMS single segment, with spigots, short with rounded terminus. Legs. Anterior two pairs noticeably more slender than posterior pairs. Leg I 8.15 long. Tarsus I with 7 trichobothria arranged in staggered row, distal aspect of row interspersed with setae. Legs I, II with light scopulae on tarsus, metatarsus; light scopulae on distal aspect tarsus legs III, IV. PTLs 27, TBs 7. Rudimentary preening comb on retrolateral distal surface, tarsus-metatarsus joint, of metatarsus III; well developed, wide preening comb on leg IV. Spermathecae. 2 short, heavily sclerotized, simple spermathecal bulbs; basal extension small (Figs 329-331).

Variation (4). Cl 4.00-6.25, 5.25 ± 0.49; Cw 3.44-5.50, 4.51 ± 0.43; STRl 2.10-3.36, 2.74 ± 0.27; STRw 1.93-3.32, 2.67 ± 0.31; LBw 0.68-1.02, 0.9 ± 0.08; LBl 0.43-0.77, 0.61 ± 0.08; Leg I: 8.15-13.68, 11.10 ± 1.15; ANTd 4-4, 4.00 ± 0; PTLs 27-36, 30.00 ± 2.12; TBs 6-8, 7.00 ± 0.41.

Material examined.

United States: California: Riverside Co.: 2.9km [road] W of Lake Mathews, Canyon just S Cajalco Rd, 33.8256, -117.4957 1, 265m, W Icenogle 22.iv.2000 [AP360, 2♀, AUMNH], 6.viii.2000 [AP367, 368, 666, 2♂, 1♀, AUMNH], 23.vii.2000 [AP667, 2♀, AUMNH], 7.vii.2000 [AP668, 1♀, AUMNH], 8.vi.2000 [AP669, 1♀, 2juv, AUMNH], 18.viii.2000 [AP670, 2♂, AUMNH], 6.ix.1999 [AP1235-1239, 12♂, AUMNH], 19.vii.1999 [AP1240, 1♀, 2juv, AUMNH], 24.ix.2002 [MY670-673, 4♂, AUMNH], 6.ix.1999 [MY3778, 1♀, 1♂, AUMNH], J Bond 20.xi.1998 [AP694, 1♀, AUMNH].

Distribution and natural history.

Aptostichus cajalco is known only from the type locality, adjacent to "Cajalco Canyon" in Riverside County. The habitat is California coastal chaparral. Males disperse in late summer and early fall (August, September) before the winter rains. A single, highly degraded specimen resembling Aptostichus cajalco was collected in a pitfall trap from the vicinity of Yucaipa, California.

Species concept applied.

Morphological.

Conservation status.

As a consequence of its very restricted distribution and apparently low abundance the conservation status of Aptostichus cajalco would likely be chara-cterized as imperiled.

The Sierra species group

Included species.

Aptostichus sierra sp. n.

Aptostichus huntington sp. n.

Aptostichus dorothealangeae sp. n.

Aptostichus chavezi sp. n.