Difference between revisions of "Aptostichus chemehuevi"

Latest revision as of 09:53, 20 December 2012

Taxonavigation

Ordo: Araneae
Familia: Euctenizidae
Genus: Aptostichus

Name

Aptostichus chemehuevi Bond, 2012 sp. n. – Wikispecies link – Chemehuevi Desert Trapdoor Spider’ ZooBank link – Pensoft Profile

Types

Male holotype and paratype (AP398) from California, San Bernardino County, Pisgah Crater, 34.7465, -116.37551, 666m, coll. Norris & Heath 17.ii.1967, deposited in AMNH.

Etymology

The specific epithet is a noun in apposition taken from the Chemehuevi Band of the Southern Paiute Native American People.

Diagnosis

Males (Fig. 228) can be diagnosed from all known species of Aptostichus by having many spines on metatarsus I that form two distinct rows and by having a linear row of multiple spines on the prolateral surface of tibia I (Figs 230-234). Males of all other known species of Aptostichus have a single row of very few spines on metatarsus I and/or have very many spines dispersed across the prolateral surface of tibia I or have only three spines composing the row.

Description of male holotype

Specimen preparation and condition. Specimen collected from pitfall, preserved in 70% EtOH. Coloration faded. Pedipalp, leg I left side removed, stored in vial with specimen. General coloration. Carapace, chelicerae, legs strong brown 7.5YR 4/6. Abdomen uniform pale brown 10YR 7/4, light markings dorsally (Fig. 228). Cephalothorax. Carapace 4.75 long, 4.15 wide, glabrous, stout black bristles along fringe; surface smooth, pars cephalica elevated. Fringe, posterior margin with black bristles. Foveal groove deep, moderately recurved. Eyes on low mound. AER slightly procurved, PER slightly recurved. PME, AME subequal diameter. Sternum moderately setose, STRl 2.91, STRw 2.33. Posterior sternal sigilla moderate in size, positioned toward center, not contiguous, anterior sigilla pairs small, oval, marginal. Chelicerae with distinct anterior tooth row comprising 6 teeth, posterior margin with single row of small denticles. Palpal endites with patch of small cuspules on proximal, inner margin, labium with 1 cuspule, LBw 0.80, LBl 0.44. Rastellum consists of 5 very stout spines arranged along anterior cheliceral margin, not on mound. Abdomen. Setose, heavy black setae intermingled with fine black setae. Legs. Leg I: 4.80, 3.40, 3.20, 1.98, 1.65; leg IV: 4.78, 2.17. Light tarsal scopulae on tarsus, metatarsus legs I, tarsus leg II. Tarsus I with single, slightly staggered row of 13 trichobothria. Leg I spination pattern illustrated in Figures 230, 231; TSp 6, TSr 4, TSrd 7. Pedipalp. Articles stout, lacking distinct spines (Fig. 229). PTw 1.02, PTl 2.17, Bl 1.04. Embolus slender, tapering sharply toward tip, without serrations (Fig. 229).
Variation (10). Cl 4.06-5.63, 4.77±0.13; Cw 3.38-4.75, 4.04±0.11; STRl 2.46-2.91, 2.69±0.05; STRw 1.77-2.49, 2.13±0.06; LBw 0.68-0.83, 0.75±0.02; LBl 0.44-0.56, 0.47±0.01; leg I: 4.19-5.44, 4.74±0.12; 2.81-3.81, 3.30±0.1; 2.79-3.50, 3.14±0.07; 1.65-2.10, 1.86±0.05; 1.53-1.86, 1.66±0.03; leg IV: 4.00-4.88, 4.53±0.09; 1.88-2.25, 2.12±0.04; PTl 1.89-2.37, 2.07±0.05; PTw 0.87-1.08, 0.96±0.02; Bl 0.98-1.20, 1.07±0.02; TSp 5-8, 6.20±0.29; TSr 4-8, 5.20±0.49; TSrd 6-9, 7.70±0.4.

Description of female

Known only from male specimens.

Material examined

United States: California: San Bernardino Co.: 29 Palms Joshua Tree National Park Headquarters, 34.1296, -116.03593, 602m, J. Freilid 9.ii.1994 [AP601, 1♂, UCR]; Pisgah Crater, 34.7465, -116.37551, 666m, Norris & Heath 11.xi.1961 [AP566, 1♂, AMNH], 17.ii.1962 [AP344, 346, 398, 349, 4♂, AMNH], 6.i.1963 [AP345, 397, 2♂, AMNH], 6.i.1967 [AP565, 1♂, AMNH], 1.ii.1961 [AP342, 347, 2♂, AMNH], 25.ii.1961 [AP343, 1♂, AMNH], 11.ii.1961 [AP348, 1♂, AMNH]; Kelso Dunes, 34.9108, -115.73033, 770m, D. Weisman 20.xii.1986 [AP340, 1♂, AMNH], V. & B. Roth 4.i.1981 [AP341, 2juv., CAS].

Distribution and natural history

Aptostichus chemehuevi is known from only three Mojave Desert localities in San Bernardino County (Map 25); despite extensive collecting efforts at the type locality females have never been collected thus little is known of this species natural history. Males appear to disperse during the winter months, November-February. This species is considered to be syntopic with Aptostichus elisabethae.

Conservation status

Although little information is available, the conservation status of Aptostichus chemehuevi is likely imperiled (also see discussion of Aptostichus elisabethae) given its paucity of specimens in collections and distribution restricted to three locations.

Species concept applied

Morphological.

Original Description

• Bond, J; 2012: Phylogenetic treatment and taxonomic revision of the trapdoor spider genus Aptostichus Simon (Araneae, Mygalomorphae, Euctenizidae) ZooKeys, 252: 1-209. doi

Images

Maps 25, 26. Aptostichus killerdana sp. n. (filled square), Aptostichus serrano sp. n. (filled circles), Aptostichus chemehuevi sp. n. (filled triangles). 25 known distributions 26 predicted distribution of Aptostichus serrano; cooler colors–blue shades–represent areas of high probability of occurrence, warmer colors–yellow and orange shades–represent areas of low probability of occurrence.  Maps 27, 28. Aptostichus aguacaliente sp. n. 27 distribution of known specimens 28 predicted distribution; cooler colors–blue shades–represent areas of high probability of occurrence, warmer colors–yellow and orange shades–represent areas of low probability of occurrence.  Figures 228–235. Aptostichus chemehuevi sp. n. male specimens; scale bars = 1.0mm. 228–231 holotype (AP398) 228 habitus 229 retrolateral aspect, pedipalp [805982] 230 retrolateral aspect, leg I [805978] 231 prolateral aspect, leg I [805980] 232, 233 paratype (AP397) retrolateral and prolateral aspects, leg I [805984, 805988] 234, 235 line drawings of leg I tibia and metatarsus spination variation.  Map 29. Distribution of Aptostichus sarlacc sp. n. (filled squares) and Aptostichus derhamgiulianii sp. n. (filled circles).