Aphonopelma saguaro Hamilton

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 : 228-230

Taxon classification Animalia Araneae Theraphosidae

Aphonopelma saguaro Hamilton sp. n. Figures 129, 130, 131, 132; Suppl. material 4

Types.

Male holotype (APH_3220) collected from Sabino Canyon, Tucson, Pima Co., Arizona, 32.322533 -110.809561 2, elev. 2774ft., 23.xi.2014, coll. Philip MacDuff; deposited in AUMNH. Paratype female (APH_3176) from Saguaro National Park - Saguaro East (Rincon Mountain District), off Cactus Forest Loop Dr., before the Mica View picnic area, Pima Co., Arizona, 32.198568 -110.735614 1, elev. 2944ft., 12.xi.2013, coll. Brent E. Hendrixson and Chris A. Hamilton; deposited in AUMNH. Paratype male (APH_2540) from Sabino Canyon, Tucson, Pima Co., Arizona, 32.316614 -110.81745 5, elev. 2818ft., date unknown, coll. O. Bryant; deposited in AMNH.

Etymology.

The specific epithet is a noun in apposition taken from type locality, Saguaro National Park, where this new species can be found in and around the foothills of the Santa Catalina and Rincon Mountains.

Diagnosis.

Aphonopelma saguaro (Fig. 129) is a member of the paloma species group and can be distinguished by a combination of morphological, molecular, and geographic characteristics. Nuclear DNA identifies Aphonopelma saguaro as a strongly supported, phylogenetically-distinct lineage (Fig. 8) that is a sister lineage to Aphonopelma mareki sp. n., Aphonopelma parvum sp. n., and Aphonopelma superstitionense sp. n. Aphonopelma saguaro can easily be differentiated from syntopic populations of Aphonopelma chalcodes , Aphonopelma catalina , and Aphonopelma vorhiesi by their smaller size, and can be differentiated from other members of the paloma species group by locality. Importantly, Aphonopelma saguaro males either possess a swollen or slightly swollen femur III, which is different from the normal femur found in Aphonopelma parvum . The most significant measurements that distinguish male Aphonopelma saguaro from its closely related phylogenetic and syntopic species are F1, Cl, and the extent of scopulation on metatarsus IV. Male Aphonopelma saguaro can be distinguished by possessing a larger Cl/M3 (≥1.17; 1.17-1.25) than Aphonopelma superstitionense (≤1.12; 1.05-1.12); a smaller F1/T3 (≤1.51; 1.42-1.51) than Aphonopelma catalina (≥1.69; 1.69-1.97) and Aphonopelma paloma (≥1.54; 1.54-1.69); a smaller Cl/PTw (≤4.27; 3.13-4.27) than Aphonopelma vorhiesi (≥4.61; 4.61-5.58); and a smaller L4 scopulation extent (14%-26%) than Aphonopelma chalcodes (42%-76%) and Aphonopelma parvum (36%-44%). There are no significant measurements that separate male Aphonopelma saguaro and Aphonopelma mareki . The most significant measurement that distinguishes female Aphonopelma saguaro from its closely related phylogenetic and syntopic species is T1. Female Aphonopelma saguaro can be distinguished by possessing a larger T1/M4 (1.02 ± (only 1 specimen)) than superstitionense (0.84 ± (only 1 specimen)); a smaller F1/T1 (1.13 ± (only 1 specimen)) than Aphonopelma catalina (≥1.21; 1.21-1.22), Aphonopelma chalcodes (≥1.25; 1.25-1.42), Aphonopelma marxi (≥1.19; 1.19-1.27), Aphonopelma parvum (≥1.18; 1.18-1.30), Aphonopelma superstitionense (1.30 ± (only 1 specimen)), and Aphonopelma vorhiesi (≥1.24; 1.24-1.32). There are no significant measurements that separate female Aphonopelma saguaro and Aphonopelma paloma .

Description of male holotype

(APH_3220; Fig. 130). Specimen preparation and condition: Specimen collected wandering and preserved in 80% ethanol; 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 I-IV removed for DNA and stored at -80°C in the AUMNH (Auburn, AL). General coloration: Faded black/brown. Cephalothorax: Carapace 6.165 mm long, 5.719 mm wide; densely clothed with faded pubescence, appressed to surface; fringe covered in longer setae not closely appressed to surface; foveal groove medium deep and recurved; pars cephalica region rises very gradually from foveal groove on a straight plane towards the ocular area; AER slightly procurved, PER very slightly recurved - mostly straight; normal sized chelicerae; clypeus extends forward on a slight curve; LBl 0.961, LBw 1.148; sternum hirsute, clothed with faded, densely packed, short setae. Abdomen: Densely clothed in short black/brown pubescence with numerous longer, lighter setae interspersed (generally red or orange in situ); 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 pubescence. Metatarsus I slightly curved. F1 6.232; F1w 1.593; P1 2.444; T1 5.62; M1 4.346; A1 3.053; F3 5.31; F3w 1.985; P3 2.071; T3 4.241; M3 4.952; A3 3.449; F4 6.314; F4w 1.736; P4 2.216; T4 5.541; M4 6.215; A4 3.704; femur III is swollen. All tarsi fully scopulate. Extent of metatarsal scopulation: leg III (SC3) = 38.0%; leg IV (SC4) = 19.2%. Three ventral spinose setae, two prolateral, and one retrolateral spinose seta on metatarsus III; seven ventral spinose setae and one retrolateral on metatarsus IV; two prolateral spinose setae and three ventral spinose setae on tibia I; one ventral spinose seta on patella I; one megaspine present on the retrolateral tibia, at the apex of the mating clasper; two megaspines on the apex on the retrolateral branch of the tibial apophyses. Coxa I: Prolateral surface covered by fine, hair-like setae. Pedipalps: Hirsute; densely clothed in the same setal color as the other legs, with numerous longer ventral setae; one spinose seta at the apical, prolateral femur; one spinose seta on the prolateral patella; four prolateral spinose setae and one ventral on the palpal tibia; PTl 3.953, PTw 1.445. Palpal bulb is very short and stout. When extended, embolus tapers with a curve to the retrolateral side; embolus slender, no keels; distinct dorsal and ventral transition from bulb to embolus.

Variation (6).Cl 4.554-6.165 (5.362 ± 0.25), Cw 4.074-5.719 (4.998 ± 0.23), LBl 0.576-0.961 (0.745 ± 0.06), LBw 0.816-1.148 (0.997 ± 0.05), F1 4.764-6.232 (5.717 ± 0.21), F1w 1.121-1.593 (1.387 ± 0.07), P1 1.732-2.444 (2.106 ± 0.1), T1 4.33-5.674 (5.158 ± 0.2), M1 3.394-4.346 (3.964 ± 0.14), A1 2.542-3.241 (2.949 ± 0.1), L1 length 16.76-21.695 (19.894 ± 0.74), F3 3.941-5.31 (4.772 ± 0.21), F3w 1.268-1.985 (1.666 ± 0.11), P3 1.481-2.071 (1.777 ± 0.09), T3 3.289-4.241 (3.892 ± 0.15), M3 3.643-4.952 (4.449 ± 0.21), A3 2.633-3.581 (3.156 ± 0.15), L3 length 14.985-20.023 (18.046 ± 0.79), F4 4.683-6.314 (5.591 ± 0.23), F4w 1.037-1.736 (1.306 ± 0.09), P4 1.541-2.216 (1.917 ± 0.09), T4 4.435-5.664 (5.152 ± 0.19), M4 4.675-6.393 (5.661 ± 0.25), A4 3.212-3.993 (3.497 ± 0.12), L4 length 18.545-23.99 (21.817 ± 0.82), PTl 3.036-3.953 (3.612 ± 0.14), PTw 1.238-1.644 (1.449 ± 0.06), SC3 ratio 0.306-0.521 (0.402 ± 0.03), SC4 ratio 0.146-0.263 (0.202 ± 0.02), Coxa I setae = fine & thin hair-like, F3 condition = slightly swollen/swollen.

Description of female paratype

(APH_3176; Fig. 131). Specimen preparation and condition: Specimen collected live from burrow, preserved in 80% ethanol; 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 I-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/brown. Cephalothorax: Carapace 6.86 mm long, 6.033 mm wide; Hirsute, densely clothed with short faded black/brown pubescence closely appressed to surface; fringe densely covered in slightly longer setae; foveal groove medium deep and recurved; pars cephalica region gently rises from thoracic furrow, arching anteriorly toward ocular area; AER slightly procurved, PER very slightly recurved; chelicerae robust, clypeus extends on a curve; LBl 1.087, LBw 1.239; sternum hirsute, clothed with short faded setae. Abdomen: Densely clothed dorsally in short 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, with capitate bulbs, short, widening towards the bases; not fused. Legs: Hirsute; densely clothed in short faded black/brown pubescence; F1 5.361; F1w 2.073; P1 2.34; T1 4.718; M1 3.253; A1 3.049; L1 length 18.721; F3 4.431; F3w 1.838; P3 2.042; T3 3.361; M3 3.261; A 3 3.124; L3 length 16.219; F4 5.828; F4w 1.782; P4 2.412; T4 4.814; M4 4.607; A4 3.521; L4 length 21.182. All tarsi fully scopulate. Extent of metatarsal scopulation: leg III (SC3) = 49.0%; leg IV (SC4) = 21.8%. Two ventral spinose setae and two prolateral spinose setae on metatarsus III; seven ventral spinose setae and one prolateral spinose seta on metatarsus IV. Coxa I: Prolateral surface covered by very thin tapered and fine, hair-like setae. Pedipalps: Densely clothed in the same setal color as the other legs; one spinose seta on the apical, prolateral femur; five prolateral spinose setae (two at the apical, prolateral border with the tarsus) and one ventral spinose seta on the tibia.

Material examined.

United States: Arizona: Pima: Sabino Canyon, Tucson, 32.316614 -110.81745 5, 2818ft., [APH_2540, date unknown, 1♂, O. Bryant, AMNH]; 32.3132 -110.811875 2, 2718ft., [APH_3219, 22/11/2014, 1♂, Philip MacDuff, AUMNH]; 32.322533 -110.809561 2, 2774ft., [APH_3220, 23/11/2014, 1♂, Philip MacDuff, AUMNH]; Bear Canyon, Tucson, 32.315814 -110.79015 2, 2857ft., [APH_3221, 3/12/2014, 1♂, Philip MacDuff, AUMNH]; 32.31655 -110.788878 2, 2871ft., [APH_3222, 3/12/2014, 1♂, Philip MacDuff, AUMNH]; 32.314594 -110.794006 2, 2814ft., [APH_3223, 3/12/2014, 1♂, Philip MacDuff, AUMNH]; Saguaro National Park, off Cactus Forest Loop Dr, before Mica View picnic area, 32.198568 -110.735614 1, 2944ft., [APH_3176, 12/11/2013, 1♀, Brent E. Hendrixson, Chris A. Hamilton, AUMNH].

Distribution and natural history.

Aphonopelma saguaro can be found inhabiting the Madrean Archipelago and Sonoran Basin and Range Level III Ecoregions in southeastern Arizona where their distribution occurs in the foothills and lower canyons of the Santa Catalina and Rincon Mountains (Fig. 132). Aphonopelma saguaro can be found in syntopy with Aphonopelma catalina , Aphonopelma chalcodes and Aphonopelma vorhiesi . The breeding season, when mature males abandon their burrows in search of females, occurs during the late fall and early winter ( November–December).

Conservation status.

Aphonopelma saguaro appears to have a limited distribution restricted to the foothills and lower canyons in and around the Santa Catalina and Rincon Mountains. As evidenced by only one specimen previously collected and deposited in a museum collection prior to this study, Aphonopelma saguaro can be difficult to find due to the cryptic nature of their burrows and narrow window of activity during the year. The Tucson Metropolitan area is experiencing rapid growth and recreational activities in the Santa Catalina and Rincon Mountains threaten suitable habitat for this species. The status of Aphonopelma saguaro seems secure (e.g., protection in Saguaro National Park) but should be monitored.

Remarks.

Other important ratios that distinguish males: Aphonopelma saguaro possess a larger T3/F4 (≥0.67; 0.67-0.71) than Aphonopelma paloma (≤0.64; 0.57-0.64) and Aphonopelma parvum (≤0.66; 0.61-0.66); a larger PTl/F4 (≥0.62; 0.62-0.66) than Aphonopelma chalcodes (≤0.62; 0.52-0.62), Aphonopelma superstitionense (≤0.59; 0.55-0.59), and Aphonopelma vorhiesi (≤0.62; 0.55-0.62); a smaller Cl/M3 (≤1.25; 1.17-1.25) than Aphonopelma catalina (≥1.26; 1.26-1.42); a smaller F1/T3 (≤1.51; 1.42-1.51) than Aphonopelma parvum (≥1.56; 1.56-1.70); a smaller Cl/PTw (≤4.27; 3.13-4.27) than Aphonopelma chalcodes (≥5.06; 5.06-6.05) and Aphonopelma superstitionense (≥4.40; 4.40-4.72); a smaller L3 scopulation extent (30%-52%) than Aphonopelma chalcodes (65%-86%), Aphonopelma parvum (60%-65%), and Aphonopelma vorhiesi (53%-62%). Other important ratios that distinguish females: Aphonopelma saguaro possess a smaller F3L/W (2.41 ± (only 1 specimen)) than Aphonopelma catalina (≥2.93; 2.93-2.99), Aphonopelma chalcodes (≥2.84; 2.84-3.15), Aphonopelma mareki (≥2.66; 2.66-3.00), Aphonopelma parvum (≥2.85; 2.85-3.05), Aphonopelma superstitionense (2.75 ± (only 1 specimen)), and Aphonopelma vorhiesi (≥2.77; 2.77-3.11). 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 other are claimed to be significant at this time (see Suppl. material 2). During evaluation of traditional two-dimensional PCA morphospace and three-dimensional PCA morphospace (PC1~PC2~PC3), males of Aphonopelma saguaro separate from Aphonopelma catalina , Aphonopelma chalcodes , Aphonopelma vorhiesi and Aphonopelma parvum , but do not separate from Aphonopelma paloma , Aphonopelma mareki , or Aphonopelma superstitionense . Female Aphonopelma saguaro separate from Aphonopelma catalina , Aphonopelma chalcodes , and Aphonopelma vorhiesi , but do not separate from Aphonopelma mareki , Aphonopelma paloma , Aphonopelma parvum , or Aphonopelma superstitionense in two-dimensional morphological space, yet when three-dimensional morphospace is plotted, Aphonopelma saguaro will separate from Aphonopelma parvum . PC1, PC2, and PC3 explain ≥98% of the variation in all analyses. While mtDNA (CO1) identifies saguaro as a unique and independent lineage, its placement with regards to its sister lineages is not well supported.