Aphonopelma mojave Prentice, 1997

Hamilton, Chris A., Hendrixson, Brent E. & Bond, Jason E., 2016, Taxonomic revision of the tarantula genus Aphonopelma Pocock, 1901 (Araneae, Mygalomorphae, Theraphosidae) within the United States, ZooKeys 560, pp. 1-340 : 187-193

Taxon classification Animalia Araneae Theraphosidae

Aphonopelma mojave Prentice, 1997 Figures 100, 101, 102, 103, 104

Aphonopelma mojave Prentice, 1997: 157; male holotype and female allotype from S of Red Mountain, 20 miles N of Kramer Jct. on Hwy 395, 1-2 miles W of Hwy 395, San Bernardino and Kern Co. line, California, 35.310573 -117.644350 4, elev. 3405ft., 28.x.1989 (male), 20.x.1991 (female), coll. Thomas R. Prentice; deposited in AMNH. [examined]

Diagnosis.

Aphonopelma mojave (Fig. 100) is a member of the paloma species group and can be identified by a combination of morphological, molecular, and geographic characteristics. Nuclear and mitochondrial DNA identifies Aphonopelma mojave as a strongly supported monophyletic lineage (Figs 7-8) that is a sister lineage to Aphonopelma atomicum sp. n., Aphonopelma icenoglei sp. n., Aphonopelma prenticei sp. n., and Aphonopelma joshua . Aphonopelma mojave can easily be distinguished from syntopic populations of Aphonopelma iodius by their smaller size and limited extent of scopulation on metatarsi III and IV, and from other members of the paloma species group by locality. The most significant measurements that distinguish male Aphonopelma mojave from its closely related phylogenetic and syntopic species are F4, PTl, and the extent of scopulation on metatarsus IV. Male Aphonopelma mojave can be distinguished by possessing a larger PTl/F4 (≥0.57; 0.57-0.62) than Aphonopelma joshua (≤0.51; 0.48-0.51); and by possessing a smaller L4 scopulation extent (30%-44%) than Aphonopelma iodius (62%-88%). There are no significant measurements that separate male Aphonopelma mojave from Aphonopelma atomicum , Aphonopelma icenoglei , or Aphonopelma prenticei , although Aphonopelma mojave males do not possess the swollen femur III condition that is known in Aphonopelma atomicum and Aphonopelma prenticei ). The most significant measurements that distinguish female Aphonopelma mojave from its closely related phylogenetic and syntopic species are Cl, F3, T3, and the extent of scopulation on metatarsus IV. Female Aphonopelma mojave can be distinguished by possessing a larger A1/F3 (≥0.56; 0.56-0.67) than Aphonopelma atomicum (≤0.56; 0.53-0.56); a larger F1/T3 (≥1.57; 1.57-1.92) than Aphonopelma joshua (≤1.57; 1.47-1.57); by possessing a smaller Cl/M4 (≤1.31; 1.20-1.31) than Aphonopelma prenticei (≥1.31; 1.31-1.52); and a smaller L4 scopulation extent (34%-52%) than Aphonopelma iodius (59%-83%). There are no significant measurements that separate female Aphonopelma mojave from Aphonopelma icenoglei . Aphonopelma mojave and Aphonopelma icenoglei are morphologically very similar but are not sister lineages (Fig. 8) and have allopatric distributions.

Description.

Male and female originally described by Prentice (1997).

Redescription of male exemplar

(APH_1561; Fig. 101). Specimen preparation and condition: Specimen collected live wandering, preserved in 80% ethanol; deposited in AUMNH; original coloration faded due to preservation. Left legs I, III, IV, and left pedipalp removed for measurements and photographs; stored in vial with specimen. Right legs III & IV removed for DNA and stored at -80°C in the AUMNH (Auburn, AL). General coloration: Faded black or brown. Cephalothorax: Carapace 7.454 mm long, 6.979 mm wide; Very hirsute; densely clothed with faded black pubescence mostly appressed to surface; fringe covered in long setae not closely appressed to surface; posterior region of carapace with long setae; foveal groove medium deep and straight; pars cephalica region rises gradually from foveal groove to ocular area; AER very slightly procurved, PER recurved; normal sized chelicerae; clypeus extends forward on a curve; LBl 1.03, LBw 1.266; sternum hirsute, clothed with faded black, densely packed, short setae. Abdomen: Densely clothed in short black pubescence with numerous longer red/orange setae interspersed; possessing a dense dorsal patch of black Type I urticating bristles ( Cooke et al. 1972) - smaller and distinct from large species. Legs: Hirsute; densely clothed in faded black pubescence. Metatarsus I straight. F1 8.246; F1w 1.77; P1 2.873; T1 7.339; M1 6.254; A1 4.705; F3 7.408; F3w 2.013; P3 2.564; T3 5.684; M3 7.373; A3 4.672; F4 8.639; F4w 1.754; P4 2.468; T4 7.362; M 4 9.201; A4 4.984; femur III is normal. All tarsi fully scopulate. Extent of metatarsal scopulation: leg III (SC3) = 64.3%; leg IV (SC4) = 34%. Two ventral and one prolateral spinose setae on metatarsus III; four ventral spinose setae and one prolateral on metatarsus IV; two prolateral spinose setae on tibia I; one large megaspine is present at the apex on the retrolateral tibia of the mating clasper. Coxa I: Prolateral surface covered by fine, hair-like setae. Pedipalps: Very hirsute, particularly ventrally; densely clothed in the same setal color as the other legs; one spinose seta near the anterior margin of the prolateral palpal femur and five spinose setae on the prolateral palpal tibia; PTl 5.132, PTw 1.612. Palpal bulb is short and stout; distinct transition between bulb and embolus; embolus tapers and gently curves to the retrolateral side, no keels.

Variation (6).Cl 7.374-8.988 (7.862 ± 0.25), Cw 6.689-8.035 (7.185 ± 0.2), LBl 1.03-1.206 (1.079 ± 0.03), LBw 1.22-1.371 (1.272 ± 0.02), F1 7.352-9.266 (8.251 ± 0.25), F1w 1.764-2.218 (1.908 ± 0.07), P1 2.873-3.421 (3.16 ± 0.08), T1 6.69-8.041 (7.323 ± 0.19), M1 6.01-7.277 (6.492 ± 0.17), A1 3.87-4.994 (4.451 ± 0.17), L1 length 27.868-32.999 (29.677 ± 0.76), F3 6.577-7.938 (7.23 ± 0.19), F3w 1.915-2.449 (2.081 ± 0.08), P3 2.537-2.931 (2.686 ± 0.07), T3 5.162-6.539 (5.683 ± 0.19), M3 6.462-7.865 (7.072 ± 0.2), A3 4.293-5.387 (4.685 ± 0.17), L3 length 25.19-30.66 (27.355 ± 0.77), F4 8.283-9.518 (8.682 ± 0.18), F4w 1.754-2.14 (1.874 ± 0.06), P4 2.468-3.188 (2.791 ± 0.11), T4 6.99-8.241 (7.506 ± 0.17), M4 8.358-9.946 (8.998 ± 0.23), A4 4.446-5.929 (4.984 ± 0.24), L4 length 30.958-36.657 (32.961 ± 0.83), PTl 4.866-5.584 (5.153 ± 0.1), PTw 1.536-2.029 (1.75 ± 0.08), SC3 ratio 0.601-0.792 (0.666 ± 0.03), SC4 ratio 0.303-0.438 (0.377 ± 0.02), Coxa I setae = very thin tapered, F3 condition = normal.

Description of female exemplar

(APH_1558; Figs 102-103). Specimen preparation and condition: Specimen collected live from burrow, preserved in 80% ethanol; deposited in AUMNH; original coloration faded due to preservation. Left legs I, III, IV, and pedipalp removed for photographs and measurements; stored in vial with specimen. Right legs III & IV removed for DNA and stored at -80°C in the AUMNH (Auburn, AL). Genital plate with spermathecae removed and cleared, stored in vial with specimen. General coloration: Faded black or brown. Cephalothorax: Carapace 7.687 mm long, 7.094 mm wide; Hirsute, densely clothed with short faded black or brown pubescence closely appressed to surface; fringe densely covered in slightly longer setae; foveal groove medium deep and slightly procurved; pars cephalica region gently rises from thoracic furrow, arching anteriorly toward ocular area; AER very slightly procurved - mostly straight, PER recurved; chelicerae slightly robust, clypeus extends forward on a curve; LBl 1.281, LBw 1.41; sternum hirsute, clothed with short faded black or brown setae. Abdomen: Densely clothed dorsally in short black, faded black setae with longer, lighter setae (generally red or orange in situ) focused near the urticating patch; dense dorsal patch of black Type I urticating bristles ( Cooke et al. 1972) - smaller and distinct from large species. Spermathecae: Paired and separate, short, with capitate bulbs and wide bases that are not fused. Legs: Hirsute; densely clothed in short faded black or brown pubescence; F1 6.846; F1w 1.957; P1 2.985; T1 5.697; M1 4.34; A1 3.591; F3 5.573; F3w 1.837; P3 2.536; T3 4.24; M3 4.45; A3 4.218; F4 7.245; F4w 1.888; P4 2.433; T4 5.975; M4 6.167; A4 4.753. All tarsi fully scopulate. Extent of metatarsal scopulation: leg III (SC3) = 76.8%; leg IV (SC4) = 34.3%. One ventral spinose seta on metatarsus III; seven ventral spinose setae on metatarsus I. Coxa I: Prolateral surface covered by fine, hair-like setae. Pedipalps: Densely clothed in the same setal color as the other legs; one spinose seta on the apical, prolateral femur, seven prolateral (three at the apical, prolateral border with the tarsus) and two ventral spinose setae on the tibia (one at the apical, ventral border with the tarsus).

Variation (7).Cl 6.911-8.471 (7.803 ± 0.21), Cw 6.203-7.648 (6.858 ± 0.2), LBl 1.071-1.48 (1.24 ± 0.05), LBw 1.263-1.70 (1.453 ± 0.06), F1 5.84-7.52 (6.877 ± 0.21), F1w 1.66-1.962 (1.873 ± 0.04), P1 2.15-3.163 (2.774 ± 0.12), T1 4.72-6.53 (5.642 ± 0.21), M1 3.73-4.66 (4.242 ± 0.12), A1 3.16-4.18 (3.588 ± 0.12), L1 length 19.6-25.75 (23.122 ± 0.72), F3 5.311-6.34 (5.747 ± 0.13), F3w 1.37-1.849 (1.666 ± 0.07), P3 2.06-2.774 (2.426 ± 0.1), T3 3.38-4.76 (4.153 ± 0.17), M3 4.05-4.87 (4.477 ± 0.12), A3 3.08-4.218 (3.737 ± 0.13), L3 length 18.14-22.45 (20.54 ± 0.56), F4 6.68-7.76 (7.196 ± 0.14), F4w 1.29-1.942 (1.771 ± 0.09), P4 2.433-2.93 (2.673 ± 0.08), T4 5.37-6.26 (5.767 ± 0.12), M4 5.68-6.65 (6.192 ± 0.14), A4 3.56-4.753 (4.238 ± 0.15), L4 length 23.73-28.17 (26.067 ± 0.56), SC3 ratio 0.653- 0.768 (0.706 ± 0.02), SC4 ratio 0.343-0.525 (0.407 ± 0.03), Coxa I setae = very thin tapered. Spermathecae variation can be seen in Figure 103.

Material examined.

United States: California: Kern: 7 miles north of Johannesburg, 35.4804 -117.654683 5, 3412ft., [APH_2669, 9/10/1968, 1♂, W. Icenogle, AMNH]; 8 miles NW San Bernardino County Line along Hwy 395, 35.469394 -117.65434 1, 3482ft., [APH_0754-0755, 4/10/2009, 2 juv, Brent E. Hendrixson, Thomas Martin, AUMNH]; 8.1 miles into Kern county on Hwy 395, 35.480904 -117.67768 4, 4003ft., [APH_2390, 20/10/1991, 1♂, T.R. Prentice, AMNH]; 8.2 miles E Hwy-14 on Hwy-58, 35.016745 -118.035457 1, 2596ft., [APH_1323-1325, 30/7/2011, 3♀, Brent E. Hendrixson, Brendon Barnes, Nate Davis, Jake Storms, AUMNH]; 9.7 miles W US-395 on Randsburg-Mojave Rd (Osdick Rd becomes Randsburg-Mojave Rd), 35.26131 -117.75031 1, 3287ft., [APH_0326-0327, 7/5/2008, 2 juv, Brent E. Hendrixson, Zach Valois, AUMNH]; along power line road west of Hwy-14, 35.462553 -117.971773 1, 3199ft., [APH_1204-1207, 31/7/2010, 4 juv, Brent E. Hendrixson, Brendon Barnes, Nate Davis, AUMNH]; E of Mojave, near Hwy 58, off Cache Creek Rd, 35.1261 -118.18484 1, 3252ft., [APH_3101, 18/7/2012, 1♀, Chris A. Hamilton, Amy Skibiel, AUMNH]; E of Mojave, near Hwy 58, off Randsburg Cutoff Rd, 35.11755 -118.15001 1, 2974ft., [APH_3102, 19/7/2012, 1♂, Chris A. Hamilton, Amy Skibiel, AUMNH]; Jawbone Canyon area, 35.32137 -118.11149 5, 2900ft., [APH_1355, 21/8/2011, 1♀, Warren Burke, AUMNH]; Ransburg-Inyokern Rd., 1 mile W of Hwy 395, 35.641784 -117.874597 5, 2855 ft., [AUMS_2530, 20/10/1991, 1♂, T.R. Prentice, AUMNH]; Sage canyon, 35.600649 -117.814267 5, 2554ft., [AUMS_2576, 26/10/1975, 1♂, Ray Jillison, AUMNH]; SE of Walker’s Pass, NE side of SR-178/ Walker’s Pass Rd, 35.62323 -117.95274 1, 3985ft., [APH_0399, 4/8/2008, 1♀, Zach Valois, AUMNH]; Walker Pass, Hwy 178, 35.687958 -118.051992 5, 4605ft., [AUMS_2526, 20/10/1990, 1♂, T.R. Prentice, AUMNH]; west Mojave, 35.04916 -118.217596 7, 2985ft., [AUMS_2462, 1997, 1♂, T.R. Prentice, AUMNH]; San Bernardino: 0.25 miles E Hwy-395 on Cuddeback Rd, 35.255317 -117.608121 1, 3016ft., [APH_1555-1556, 25/10/2012, 1♀, 1 juv, Brent E. Hendrixson, AUMNH]; 10 to 17 miles S of Johannesburg, 35.172459 -117.59183 5, 2787ft., [AUMS_3317, 10/10/1974, 1♂, W. Icenogle, AUMNH]; [APH_2403, 10/10/1974, 1♀, W. Icenogle, AMNH]; [APH_2406, 10/10/1974, 1♂, W. Icenogle, AMNH]; 8.1 miles south of Kelso on Kelbaker Rd., 34.899855 -115.649338 4, 2825ft., [APH_2439, 1/11/1992, 1♂, T.R. Prentice, AMNH]; Red Mountain, 35.358297 -117.616726 6, 3609ft., [AUMS_2513, 14/10/1990, 1♀, T.R. Prentice, AUMNH]; [AUMS_2527, 20/10/1994, 1♀, Geogr, AUMNH]; Red Mountain, 1 mile west of Powerline Rd., 35.128369 -116.794985 4, 1972ft., [APH_2413, 26/10/1991, 1♂, T.R. Prentice, AMNH]; Red Mountain, 1.2 miles west of 20 Mule Team Rd., 35.247194 -117.652967 4, 3005ft., [APH_2412, 26/10/1991, 1♂, T.R. Prentice, AMNH]; Red Mountain, 19 miles N of Kramer Junction, 35.254038 -117.553643 5, 3262ft., [AUMS_2514, 3/10/1992, 1♂, T.R. Prentice, AUMNH]; [AUMS_2535, 13/10/1991, 1♂, T.R. Prentice, AUMNH]; [APH_2388, 28/10/1989, 1♂, T.R. Prentice, AMNH]; [APH_2405, 25/1/1992, 1♀, T.R. Prentice, AMNH]; [APH_2407, 13/10/1997, 1♀, T.R. Prentice, AMNH]; [APH_2408, 26/10/1991, 1♂, T.R. Prentice, AMNH]; [APH_2410, 14/10/1991, 1♂, T.R. Prentice, AMNH]; [APH_2411, 20/10/1991, 1♀, T.R. Prentice, AMNH]; [APH_2414, 26/10/1991, 1♂, T.R. Prentice, AMNH]; Red Mountain, 20 miles N of Kramer Junction, 35.301692 -117.614683 5, 3220ft., [AUMS_2510, 16/10/1992, 1 juv, T.R. Prentice, AUMNH]; Red Mountain, 20 miles N of Kramer Junction, Hwy 395, W side, 35.305756 -117.615541 5, 3256ft., [AUMS_2512, 4/10/1992, 1♂, T.R. Prentice, AUMNH]; Red Mountain, campsite W of power line road, 35.331378 -117.612816 5, 3389ft., [AUMS_2364, 20/10/1991, 1♂, T.R. Prentice, AUMNH]; Red Mountain, campsite, 19 miles north, 35.358297 -117.616726 5, 3602ft., [APH_2404, 4/10/1992, 1♀, T.R. Prentice, AMNH]; Red Mountain, junction of 20 Mule Team Rd. and PL Rd., 35.25197 -117.611916 5, 2999ft., [APH_2409, 26/10/1991, 1♂, T.R. Prentice, AMNH]; Red Mountain, South of Power Line Road, 35.321067 -117.611791 5, 3409ft., [AUMS_2531, 28/10/1989, 1♂, T.R. Prentice, AUMNH]; W of Hwy 395 along Twenty Mule Team Pkwy, 35.253597 -117.615238 1, 3013ft., [APH_1558-1561, 25/10/2012, 2♀, 2♂, Brent E. Hendrixson, AUMNH].

Distribution and natural history.

The redefined Aphonopelma mojave has a narrow distribution centered on the western Mojave Desert and extreme southeastern foothills of the Sierra Nevada Mountains in eastern Kern and northwestern San Bernardino Counties, California (Fig. 104), inhabiting the Western Mojave Basins Level III Ecoregion. Accurately georeferenced specimens have been collected at elevations between 775 and 1225 meters. The species distribution model suggests that suitable habitat may be present in adjacent sections of southwestern Inyo and northeastern Los Angeles Counties (Fig. 104B). Additional sampling is required to assess the northern extent of the distribution of Aphonopelma mojave along the Highway-395 corridor. Aphonopelma mojave is syntopic with Aphonopelma iodius (burrows of both species have been located within one meter of each other) and may overlap its range with Aphonopelma icenoglei in the vicinity of Kramer Junction. Burrow entrances are generally surrounded by a distinct mound or turret made of excavated soil and silk (Fig. 2 D–E). Mating takes place during daylight hours in the autumn (October-November). The natural history of Aphonopelma mojave and its close relatives is discussed in more detail in Prentice (1997).

Conservation status.

In addition to having a relatively narrow distribution, habitat degradation due to Off-Highway Vehicle (OHV) recreational activity probably poses the greatest threat to Aphonopelma mojave . However, these spiders are abundant (especially near the type locality), with several areas within the western Mojave Desert that are managed by the State of California or Bureau of Land Management (e.g., West Mojave Desert Ecological Reserve, Fremont Valley Ecological Reserve, Red Rock Canyon State Park, Desert Tortoise Natural Area). This species is likely secure.

Remarks.

Prentice (1997) noted that Aphonopelma mojave comprised two different geographic “races” (i.e., western and eastern lineages) but he did not describe two different species. Our results (also see Hendrixson et al. 2013, Graham et al. 2015) demonstrate that these two populations are indeed distinct species, but perhaps even more interesting is that the western and eastern groups comprise additional species-level diversity. We now recognize four different species that were all previously considered Aphonopelma mojave ( Aphonopelma atomicum , Aphonopelma icenoglei , Aphonopelma mojave , and Aphonopelma prenticei ). For both males and females, certain morphometrics have potential to be useful, though due to the amounts of variation, small number of specimens, and the small differences between species, no others are claimed to be significant at this time (see Suppl. material 2). During evaluation of traditional PCA morphospace and three-dimensional PCA morphospace (PC1~PC2~PC3), males of Aphonopelma mojave separate in morphological space from Aphonopelma iodius , Aphonopelma joshua , and Aphonopelma xwalxwal , but do not separate from Aphonopelma atomicum , Aphonopelma icenoglei , and Aphonopelma prenticei . Female Aphonopelma mojave separate from Aphonopelma iodius in morphological space, but do not separate from Aphonopelma atomicum , Aphonopelma icenoglei , and Aphonopelma prenticei . There are no known female Aphonopelma xwalxwal at this time to compare. PC1, PC2, and PC3 explain ≥96% of the variation in all analyses.