Aphonopelma paloma Prentice, 1993

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 : 193-200

Taxon classification Animalia Araneae Theraphosidae

Aphonopelma paloma Prentice, 1993 Figures 105, 106, 107, 108, 109, 110, 111

Aphonopelma paloma Prentice, 1993: 189; male holotype and female allotype from 3 miles NE exit 151 off I-8 (jct with Hwy 84), Pinal Co., Arizona, 32.856167 -112.086609 2, elev. 4310ft., 17-18.xi.1989, coll. Tom Prentice; deposited in AMNH. [examined]

Apachepelma paloma Smith, 1995: 45.

Aphonopelma paloma Prentice, 1997: 140.

Diagnosis.

Aphonopelma paloma (Fig. 105) 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 paloma as a strongly supported monophyletic lineage (Figs 7-8) supported as the sister lineage to all other members of the paloma species group. Aphonopelma paloma is the smallest species in the United States (Fig. 106) and can easily be differentiated from syntopic species by its much smaller size and reduced extent of scopulation on metatarsi III and IV; it can be distinguished from other members of the paloma species group by locality. The most significant measurements that distinguish male Aphonopelma paloma from its closely related phylogenetic and syntopic species are M1 and the extent of scopulation of metatarsus III. Male Aphonopelma paloma can be distinguished by possessing a larger M1/T3 (≥1.11; 1.11-1.16) than Aphonopelma parvum sp. n. (≤1.09; 0.99-1.09), Aphonopelma saguaro sp. n. (≤1.05; 0.99-1.05), Aphonopelma superstitionense sp. n. (≤1.04; 0.98-1.04), and Aphonopelma xwalxwal sp. n. (≤1.11; 1.09-1.11); and by possessing a smaller L3 scopulation extent (21%-41%) than Aphonopelma chalcodes (75%-86%), Aphonopelma mareki sp. n. (50%-56%), and Aphonopelma vorhiesi (44%-62%). The most significant measurements that distinguish female Aphonopelma paloma from its closely related phylogenetic and syntopic species are Cl and the extent of scopulation on metatarsus IV. Female Aphonopelma paloma can be distinguished by possessing a smaller L4 scopulation extent (0-25%) than Aphonopelma chalcodes (63%-81%), Aphonopelma parvum (33%-42%), and Aphonopelma vorhiesi (26%-37%); and by possessing a larger Cl/M4 (≥1.44; 1.44-1.60) than Aphonopelma superstitionense (1.25 ± (only 1 specimen)). There are no significant measurements that separate female Aphonopelma paloma from Aphonopelma mareki or Aphonopelma saguaro .

Description.

Male and female originally described by Prentice (1993).

Redescription of male exemplar

(APH_1603; Fig. 107). 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 grey. Cephalothorax: Carapace 5.13 mm long, 4.73 mm wide; Very hirsute; densely clothed with grey pubescence mostly appressed to surface; fringe covered in long setae not closely appressed to surface; posterior region of carapace with long, stout setae; foveal groove medium deep and straight; pars cephalica region rises gradually from foveal groove to ocular area; AER very slightly procurved - mostly straight, PER straight; normal sized chelicerae; clypeus extends forward on a curve; LBl 0.732, LBw 0.878; sternum hirsute, clothed with grey, densely packed 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 grey or faded black pubescence. Metatarsus I curved. F1 5.417; F1w 1.246; P1 2.083; T1 4.034; M1 4.058; A1 2.838; F3 4.565; F3w 1.74; P3 1.648; T3 3.51; M3 4.367; A3 2.884; F4 5.508; F4w 1.386; P4 1.733; T4 4.72; M4 5.454; A4 3.264; femur III is swollen. All tarsi fully scopulate. Extent of metatarsal scopulation: leg III (SC3) = 36.8%; leg IV (SC4) = 9.4%. Two ventral and two prolateral spinose setae on metatarsus III, with numerous medium stout setae throughout; five ventral spinose setae and one prolateral on metatarsus IV, with numerous medium stout setae throughout; two prolateral spinose setae on tibia I, one ventral spinose seta at the posterior margin of tibia I; one large megaspine is present at the apex on the retrolateral tibia of the mating clasper; one large megaspine at the apex of the retrolateral branch 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; one spinose seta on the ventral palpal tibia, with numerous medium stout setae throughout; PTl 3.619, PTw 1.329. Palpal bulb is very short and stout; embolus tapers and gently curves to the retrolateral side, no keels; distinct dorsal and ventral transition from bulb to embolus.

Variation (6).Cl 5.126-5.502 (5.343 ± 0.06), Cw 4.468-5.124 (4.824 ± 0.1), LBl 0.675-0.797 (0.741 ± 0.02), LBw 0.868-0.898 (0.878 ± 0), F1 5.289-6.208 (5.723 ± 0.15), F1w 1.176-1.402 (1.27 ± 0.04), P1 1.741-2.44 (2.047 ± 0.1), T1 4.034-5.248 (4.839 ± 0.18), M1 3.62-4.297 (4.017 ± 0.11), A1 2.785-2.876 (2.827 ± 0.01), L1 length 18.374-20.949 (19.453 ± 0.47), F3 4.466-4.958 (4.737 ± 0.08), F3w 1.456-1.831 (1.673 ± 0.06), P3 1.528-1.804 (1.694 ± 0.04), T3 3.244-3.795 (3.532 ± 0.09), M3 4.019-4.569 (4.332 ± 0.09), A3 2.658-3.047 (2.837 ± 0.06), L3 length 15.988-17.891 (17.131 ± 0.33), F4 5.308-5.984 (5.703 ± 0.11), F4w 1.112-1.445 (1.313 ± 0.05), P4 1.532-2.102 (1.829 ± 0.08), T4 4.578-5.096 (4.847 ± 0.08), M4 5.412-6.102 (5.71 ± 0.13), A4 3.042-3.374 (3.28 ± 0.05), L4 length 20.357-22.272 (21.37 ± 0.4), PTl 3.273-3.706 (3.53 ± 0.07), PTw 1.159-1.431 (1.263 ± 0.04), SC3 ratio 0.219-0.41 (0.309 ± 0.03), SC4 ratio 0.056-0.245 (0.12 ± 0.03), Coxa I setae = very thin tapered, F3 condition = swollen/slightly swollen.

Description of female exemplar

(APH_1255; Figs 108-110). 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: Grey. Cephalothorax: Carapace 5.141 mm long, 4.393 mm wide; Hirsute, densely clothed with short grey pubescence closely appressed to surface, with short, stout setae throughout; fringe densely covered in slightly longer setae; foveal groove medium deep and procurved; pars cephalica region gently rises from thoracic furrow, arching anteriorly toward ocular area; AER very procurved, PER very slightly recurved; anterior margin of carapace broad, robust chelicerae, clypeus extends forward on a curve; LBl 0.807, LBw 0.963; sternum hirsute, clothed with short grey setae. Abdomen: Densely clothed dorsally in short black, faded black, and grey setae with longer, lighter setae (generally red or orange in situ) focused near the urticating patch; small but dense dorsal patch of black Type I urticating bristles ( Cooke et al. 1972) - smaller and distinct from large species. Spermathecae: Paired and separate, short, very simple, with capitate bulbs and wide bases that are not fused. Legs: Hirsute; densely clothed in short grey pubescence; F1 4.192; F1w 1.303; P1 1.748; T1 3.323; M1 2.151; A1 2.074; F3 3.249; F3w 1.123; P3 1.463; T3 2.154; M3 2.25; A3 2.102; F4 4.301; F4w 1.181; P4 1.634; T4 3.248; M4 3.27; A4 2.408. All tarsi fully scopulate. Extent of metatarsal scopulation: leg III (SC3) = 29.1%; leg IV (SC4) = 9.7%. Three ventral spinose setae and one prolateral on metatarsus III, with numerous thicker setae throughout; three ventral spinose setae and one prolateral on metatarsus IV, with numerous thicker setae throughout. Coxa I: Prolateral surface covered by fine, hair-like setae. Pedipalps: Densely clothed in the same setal color as the other legs; two spinose setae on the anterior margin of prolateral/ventral tibia, with numerous thicker setae throughout.

Variation (12).Cl 4.635-7.058 (5.66 ± 0.24), Cw 4.192-6.092 (5.023 ± 0.21), LBl 0.763-1.197 (0.904 ± 0.04), LBw 0.903-1.346 (1.074 ± 0.04), F1 3.597-5.573 (4.52 ± 0.19), F1w 1.186-1.884 (1.508 ± 0.07), P1 1.494-2.461 (1.971 ± 0.09), T1 2.968-4.516 (3.726 ± 0.14), M1 1.911-3.189 (2.499 ± 0.12), A1 1.927-2.705 (2.295 ± 0.08), L1 length 11.984-18.261 (15.01 ± 0.61), F3 2.973-4.507 (3.635 ± 0.16), F3w 1.037-1.809 (1.346 ± 0.07), P3 1.318-2.141 (1.687 ± 0.08), T3 2.035-3.057 (2.523 ± 0.1), M3 2.067-3.361 (2.607 ± 0.13), A3 2.031-2.976 (2.401 ± 0.09), L3 length 10.438-15.884 (12.853 ± 0.55), F4 3.883-5.675 (4.735 ± 0.18), F4w 1.088-1.864 (1.374 ± 0.07), P 4 1.521-2.33 (1.911 ± 0.09), T4 3.135-4.529 (3.799 ± 0.14), M4 3.083-4.612 (3.718 ± 0.16), A4 2.308-3.263 (2.741 ± 0.1), L4 length 13.93-20.232 (16.904 ± 0.65), SC3 ratio 0.26-0.496 (0.392 ± 0.02), SC4 ratio 0-0.247 (0.169 ± 0.02), Coxa I setae = very thin tapered. Spermathecae variation can be seen in Figures 109-110.

Material examined.

United States: Arizona: Maricopa: 1.2 miles S Aqueduct on Aguila-Wickenburg Rd, 33.571504 -112.818108 1, 1306ft., [APH_0432, 16/11/2008, 1 juv, Brent E. Hendrixson, AUMNH]; 4.65 miles N I-8 (Sentinel) on Agua Caliente Rd, 32.908339 -113.262179 1, 584ft., [APH_0430, 16/11/2008, 1 juv, Brent E. Hendrixson, AUMNH]; just NW of Jct. Vulture Mine Rd and Aguila Rd, 33.719699 -112.8824 1, 1716ft., [APH_1612-1613, 12/11/2012, 2♂, Brent E. Hendrixson, AUMNH]; just S of White Tank Mtn Rd, 33.56397 -112.49147 2, 1360ft., [APH_1101-1103, 30/11/2009, 3 juv, June Olberding, AUMNH]; Pima: 0.75 miles S Ball Rd in Why along Hwy-85, 32.25235 -112.745206 1, 1765ft., [APH_0424, 15/11/2008, 1 juv, Brent E. Hendrixson, AUMNH]; [APH_0426-0427, 15/11/2008, 1♀, 1♂, Brent E. Hendrixson, AUMNH]; Bates Well Rd, S of Ajo, 32.27002 -112.86087 2, 1673ft., [APH_1114-1116, 15/12/2009, 2♀, 1♂, June Olberding, AUMNH]; in desert east of Bates Well Rd, about 7 miles W of Why, AZ, 32.28612 -112.85435 4, 1720ft., [APH_0442-0449, 12/2008, 3♀, 5 juv, June Olberding, AUMNH]; Tucson area, near Catalina State Park, N side of Tangerine Rd and E of Tangerine Crossing, E of Marana, 32.42413 -111.03427 1, 2631ft., [APH_3170-3172, 12/11/2013, 3♀, Chris A. Hamilton, Brent E. Hendrixson, AUMNH]; W of Why, 32.26683 -112.847 2, 1650ft., [APH_1253-1258, 1/12/2010, 2♂, 4♀, June Olberding, AUMNH]; Saguaro National Park (West) - western portion, 32.32247 -111.12608 2, 2790ft., [APH_1675, 1/12/14, 1♂, Derrick Smith, AUMNH; Pinal: 0.7 miles S Skyline Dr. on Quail Run Ln, 33.180864 -111.496516 2, 1552ft., [APH_1671-1674, 6/12/2012, 4♀, June Olberding, Tim Cota, AUMNH]; in desert NW jct of Hwy-84 and Amarillo Valley Rd (3.2 miles NW I-8), 32.856511 -112.085564 1, 1541ft., [APH_0421-0423, 15/11/2008, 3 juv, Brent E. Hendrixson, Paul Marek, Charity Hall, Kojun, AUMNH]; [APH_1603-1606, 10/11/2012, 3♂, 1♀, Brent E. Hendrixson, AUMNH]; off Florence-Kelvin Hwy, BLM land E of Florence, 32.99957 -111.26484 1, 1968ft., [APH_3195, 15/11/2013, 1♀, Chris A. Hamilton, Brent E. Hendrixson, AUMNH]; [APH_3197-3198, 15/11/2013, 2♀, Chris A. Hamilton, Brent E. Hendrixson, AUMNH]; off Hwy 79 around 1/2 way between 77 split and Florence at Tom Mix Rest Area, 32.818271 -111.204751 1, 2338ft., [APH_3194, 15/11/2013, 1♀, Brent E. Hendrixson, Chris A. Hamilton, AUMNH]; off Hwy 79, E side of road, N of Tucson past Hwy 77 split, near Ninety Six hills, 32.682347 -111.072531 1, 2972ft., [APH_3189-3190, 14/11/2013, 2♀, Chris A. Hamilton, Brent E. Hendrixson, AUMNH]; W of Chuck’s Corner off S. Amarillo Valley Rd, off Hwy 84, N of I-8, 32.85665 -112.08419 1, 1501ft., [APH_3166, 11/11/2013, 1♀, Brent E. Hendrixson, Chris A. Hamilton, AUMNH]; [APH_3168, 11/11/2013, 1 juv, Chris A. Hamilton, Brent E. Hendrixson, AUMNH].

Distribution and natural history.

Aphonopelma paloma is widely distributed across lower elevation sections of southern and southwestern Arizona (Figs 1G, 111) in the Sonoran Basin and Range Level III Ecoregion. Aphonopelma paloma can be found in syntopy with Aphonopelma chalcodes throughout its entire distribution and with Aphonopelma vorhiesi north of Tucson. The breeding season, when mature males abandon their burrows in search of females, is limited to late fall and early winter ( November–December). Burrow entrances of Aphonopelma paloma are unique among species in the United States in that individuals frequently create a distinct crescent-shaped mound made from excavated soil and silk (Fig. 2F); this behavior has not been observed in other similar species (e.g., Aphonopelma mareki , Aphonopelma parvum , Aphonopelma saguaro , and Aphonopelma superstitionense ). The natural history of Aphonopelma paloma is discussed in more detail by Prentice (1993).

Conservation status.

Aphonopelma paloma is abundant throughout its distribution but can be difficult to find due to the cryptic nature of their burrows and narrow window of activity during the year. This species is secure.

Remarks.

Other important ratios that distinguish Aphonopelma paloma males: possess a smaller L3 scopulation extent (21%-41%) than Aphonopelma parvum (60%-65%) and Aphonopelma xwalxwal (65%-95%); by possessing a larger PTl/M1 (≥0.81; 0.81-0.92) than Aphonopelma chalcodes (≤0.75; 0.67-0.75) and Aphonopelma xwalxwal (≤0.64; 0.57-0.64); by possessing a larger M3/A3 (≥1.46; 1.46-1.61) than Aphonopelma mareki (≤1.42; 1.27-1.42) and Aphonopelma parvum (≤1.41; 1.21-1.41), but smaller than Aphonopelma xwalxwal (≥1.66; 1.66-1.91); by possessing a larger Cl/M3 (≥1.17; 1.17-1.31) than Aphonopelma superstitionense (≤1.12; 1.05-1.12) and Aphonopelma xwalxwal (≤1.01; 0.91-1.01). Other important ratios that distinguish females: Aphonopelma paloma possess a larger Cl/A4 (≥1.92; 1.92-2.21) than Aphonopelma parvum (≤1.91; 1.63-1.91), but smaller than Aphonopelma chalcodes (≥2.32; 2.32-2.64); by possessing a smaller L3 scopulation extent (25%-50%) than Aphonopelma chalcodes (78%-93%), Aphonopelma parvum (62-67%), Aphonopelma superstitionense (64% ± (only 1 specimen)), and Aphonopelma vorhiesi (49%-69%, with slight overlap). 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, males of Aphonopelma paloma separate in PCA morphological space from Aphonopelma chalcodes , Aphonopelma vorhiesi , Aphonopelma parvum , and Aphonopelma xwalxwal but do not separate from Aphonopelma mareki , Aphonopelma saguaro , and Aphonopelma superstitionense . Female Aphonopelma paloma separate from Aphonopelma chalcodes , Aphonopelma mareki , Aphonopelma parvum , Aphonopelma saguaro , Aphonopelma superstitionense , and Aphonopelma vorhiesi in morphological space. Interestingly, Aphonopelma paloma males separate from Aphonopelma chalcodes , Aphonopelma parvum , Aphonopelma superstitionense , and Aphonopelma vorhiesi in three-dimensional PCA morphospace (PC1~PC2~PC3), but do not separate from Aphonopelma mareki or Aphonopelma saguaro . Aphonopelma paloma females separate from Aphonopelma chalcodes , Aphonopelma mareki , Aphonopelma parvum , Aphonopelma saguaro , Aphonopelma superstitionense , and Aphonopelma vorhiesi . PC1, PC2, and PC3 explain ≥96% of the variation in all analyses.