Aptostichus serrano, 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 : 108-112

Aptostichus serrano sp. n. Figures 215-219Map 25, 26

Types.

Male holotype (AP395) and male paratype (AP396) from California, Riverside County, Joshua Tree National Park, Pleasant Valley, 33.9102, -115.9931 3, 1066m, coll. E. Sleeper & S. Jenkins 20.iii.1966 & 8.i.1966, deposited in AMNH; Female paratypes (AP712, 714) from California, San Bernardino Co., Joshua Tree National Park, ~2.7km S of bend in road, HWY 62, 34.08667, -115.47778 1, 684m, coll. J. Bond & W. Icenogle 17.i.1997, deposited in AUMNH.

Etymology.

The specific epithet is a noun in apposition taken from the Serrano Native American Tribal group, which once resided throughout what are now the California counties of Riverside and San Bernardino.

Diagnosis.

Males (Fig. 215) are easily distinguished from the other known sympatric species of Aptostichus , Aptostichus bonoi , by lacking spines on the ventral surface of tarsus I (Fig. 216). The TSrd spination of Aptostichus serrano (Fig. 216) is most similar to that of Aptostichus atomarius , however male Aptostichus serrano individuals can be distinguished by having a retrolaterally offset rastellar spine. Female Aptostichus serrano individuals can be distinguished from Aptostichus atomarius females by virtue of their smaller size and a rastellar configuration similar to that of the males. Male and females are both lighter in coloration and lack the distinct mottled striping of the non-desert species (Fig. 215).

Description of male holotype.

Specimen preparation and condition. Specimen presumed to have been collected live from a pitfall trap array, preserved in 70% EtOH. Coloration lightly faded. Pedipalp, leg I left side removed, stored in vial with specimen. General coloration. Carapace, chelicerae, legs strong brown 7.5YR 4/6. Abdomen dorsally light yellowish brown 10YR 6/4, light mid dorsal stripes (Fig. 215), ventral aspect similar coloration. Cephalothorax. Carapace 4.75 long, 4.06 wide, lightly hirsute, thin white spines, stout black bristles along fringe; surface smooth, pars cephalica elevated. Fringe, posterior margin with black bristles. Foveal groove deep, straight, almost forming a pit. Eyes on low mound. AER slightly procurved, PER slightly recurved. PME, AME subequal diameter. Sternum moderately setose, STRl 2.63, STRw 2.40. Posterior sternal sigilla moderate in size, positioned mid to central, not contiguous, anterior sigilla pairs small, oval, marginal. Chelicerae with distinct anterior tooth row comprising 5 teeth, posterior margin with row of small denticles. Palpal endites with patch of small cuspules on proximal, inner margin, labium with 3 cuspules, LBw 0.77, LBl 0.41. Rastellum consists of 5 stout spines not on prominent mound, one spine offset laterally. Abdomen. Setose, heavy black setae intermingled with fine black setae. Legs. Leg I: 4.85, 3.50, 3.10, 1.90, 1.75; leg IV: 4.69, 2.44. Light tarsal scopulae on legs I, II. Tarsus I with single, staggered row of 11 trichobothria. Leg I spination pattern illustrated in Figures 216, 217; TSp 5, TSr 4, TSrd 6. Pedipalp. Articles stout, lacking distinct spines (Fig. 218). PTw 0.80, PTl 2.03, Bl 0.96. Embolus slender, slight curvature at midpoint, lacking serrations (Fig. 218).

Variation (7). Cl 4.44-5.00, 4.73 ± 0.1; Cw 3.54-4.13, 3.93 ± 0.08; STRl 2.40-2.76, 2.60 ± 0.05; STRw 1.98-2.40, 2.22 ± 0.05; LBw 0.68-0.83, 0.75 ± 0.02; LBl 0.39-0.45, 0.43 ± 0.01; leg I: 4.50-5.13, 4.81 ± 0.08; 3.25-3.56, 3.39 ± 0.05; 2.73-3.15, 2.95 ± 0.07; 1.80-2.04, 1.90 ± 0.03; 1.50-3.25, 1.89 ± 0.23; leg IV: 4.38-4.88, 4.59 ± 0.07; 2.13-2.44, 2.28 ± 0.04; PTl 1.86-2.10, 2.01 ± 0.03; PTw 0.69-0.80, 0.75 ± 0.01; Bl 0.90-1.02, 0.95 ± 0.01; TSp 3-8, 4.29 ± 0.68; TSr 2-4, 3.00 ± 0.31; TSrd 4-6, 4.71 ± 0.29.

Description of female paratype (AP712).Specimen preparation and condition. Female collected live from burrow, prepared in same manner as male holotype. Genital plate removed, cleared in trypsin, stored in microvial with specimen. General coloration. Carapace, legs, chelicerae, yellowish brown 10YR 5/4. Abdomen uniform pale brown 10YR 6/3, markings similar to males; recently collected specimens slightly darker in coloration. Cephalothorax. Carapace 4.05 long, 3.60 wide, generally glabrous with light thin setae; generally smooth surface, pars cephalica moderately elevated. Fringe lacks setae. Foveal groove deep, slightly procurved. Eye group slightly elevated on low mound. AER slightly procurved, PER slightly recurved. PME-AME subequal diameter. Sternum widest at coxae II/III, moderately setose, STRl 2.63, STRw 2.29. Three pairs of sternal sigilla anterior pairs small, oval, marginal, posterior pair larger, oval, mesially positioned but not contiguous. Chelicerae anterior tooth row comprising 6 teeth with posterior margin denticle patch. Palpal endites with 23 cuspules concentrated at inner (promargin) posterior heel; labium with 3 cuspules, LBw 0.95, LBl 0.49. Rastellum consists of 6 very stout spines positioned not on mound, one spine offset laterally; 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 10.44 long. Tarsus I with single staggered row of 10 trichobothria. Legs I, II, with moderately light scopulae on tarsi, metatarsi, legs III, IV with light tarsal scopulae. PTLs 9, TBs 3. Rudimentary preening comb on retrolateral distal surface (at tarsus - metatarsus joint) of metatarsus III, IV. Spermathecae. 2 simple spermathecal bulbs with elongate neck, small lateral basal extension (Fig. 219).

Variation (5). Cl 3.52-5.00, 4.29 ± 0.31; Cw 2.73-4.20, 3.60 ± 0.28; STRl 2.30-3.10, 2.70 ± 0.16; STRw 1.70-2.50, 2.18 ± 0.15; LBw 0.77-1.00, 0.92 ± 0.04; LBl 0.44-0.51, 0.48 ± 0.02; Leg I: 8.45-12.23, 10.67 ± 0.73; ANTd 5-6, 5.80 ± 0.22; PTLs 8-12, 10.2 ± 0.89; TBs 2-4, 3.00 ± 0.35.

Material examined.

United States: California: Riverside Co.: Joshua Tree Natl Park, Turkey Flats, jct main rd & Black Eagle Rd, 33.8283, -115.7586 1, 738m, J Bond 11.xii.1997 [AP672, 674, 679, 683, 687, 5juv, AUMNH]; Joshua Tree Natl Park, Pleasant Valley, 33.9102, -115.9931 4, 1066m, E Sleeper, S Jenkins 20.iii.1965 [AP395, 535, 2♂, AMNH], 8.i.1966 [AP396, 1♂, AMNH], 8.i.1965 [AP542, 1♂, AMNH], 26.iii.1966 [AP532, 1♀, AMNH], 7.i.1967 [AP536, 2♂, AMNH], 4.ii.1967 [AP541, 1♂, AMNH]; Quail Guzzler, Pleasant Valley, 33.9114, -116.0628 4, 1016m, E Sleeper, S Jenkins 29.vii.1966 [AP568, 1♂, CAS]; Joshua Tree Natl Park, 1.3km S Squaw Tanks, 33.9185, -116.0785 4, 1036m, E Sleeper, S Jenkins 20.iii.1965 [AP539, 1♂, AMNH]; 1.1km S Squaw Tanks, 33.9198, -116.0779 4, 1036m, 18.xii.1965 [AP540, 1juv, AMNH]; Pinto Wells, 33.9408, -115.4161 4, 305m, W Sakai 17.iii.1996 [AP599, 1♂, UCR]; Joshua Tree Natl Park, Pinyon Wells, 33.9642, -116.2472 5, 1364m, E Sleeper 7.iv.1968 [AP530, 1♀, AMNH], E Sleeper, S Jenkins 4.iii.1967 [AP534, 1♂, AMNH]; San Bernardino Co.: Joshua Tree Natl Park, Lower Covington Flat, 34.0401, -116.3102 4, 1433m, E Sleeper 16.ii.1962 [AP531, 1♂, AMNH], E Sleeper, S Jenkins 20.iii.1965 [AP533, 538, 2♂, AMNH]; Pisgah Crater, 34.7465, -116.3755 1, 666m, Norris, Heath 11.ii.1961 [AP567, 620, 2♂, AMNH]; Joshua Tree Natl Park, ~2.7km S of bend in road, hwy 62, 34.0866, -115.4777 1, 684m, J Bond, W Icenogle 17.i.1997 [AP712, 714, 2♀, 2juv, AUMNH]; NE Pinto Mountains, 34.0866, -115.4777 5, 610m, W Icenogle, T Prentice 7.ii.1991 [AP394, 1♀, CAS].

Distribution and natural history.

Aptostichus serrano is a Mojave Desert endemic that has been collected in Riverside and San Bernardino Counties. Males apparently disperse during the later winter months, January–March. The DM indicates the species is probably more spread throughout the Mojave.

Conservation status.

The conservation status of Aptostichus serrano is considered to be secure because it is widespread and found in areas that are generally well protected (e.g., Joshua Tree National Park).

Species concept applied.

Morphological.