Actinopus patagonia, Ríos-Tamayo & Goloboff, 2018

Ríos-Tamayo, D. & Goloboff, P. A., 2018, Taxonomic Revision And Morphology Of The Trapdoor Spider Genus Actinopus (Mygalomorphae: Actinopodidae) In Argentina, Bulletin of the American Museum of Natural History 2018 (419), pp. 1-84 : 59-61

Actinopus patagonia , sp. nov.

Figures 29A–H, 30A–E, 45

TYPE MATERIAL: HOLOTYPE ♂ (MACN-Ar 27097): Buenos Aires. Salina Las Barrancas [38°48′ S 62°57′ W], Apr. 1960, no collector, 1♂. PARATYPES: Chubut. 1♀ (MACN-Ar 27100), Isla de los Guanacos, Caleta Valdés (Península de

Valdés ) [42°28′ S 63°37′ W], 27 Dec. 1981, P. Domínguez and P. Goloboff ; same data and collector, 4♀ (MACN-Ar 27091). La Pampa. Las Gaviotas, Caleu Caleu [38°43′ S 63°46′ W], 26 Apr. 2007, Tizón, 1♂ ( LZI 0128 ) .

ETYMOLOGY: The specific epithet is a noun in apposition concerning the region where the species occurs.

DIAGNOSIS: A. patagonia can by recognized by their large size. Females can be distinguished by having large spermathecae (fig. 30C, D), wide and subquadrate, with irregular apical lobes. They differ from A. szumikae , A. argenteus , A. casuhati , and A. cordobensis by the lighter color of their booklung markings. Males can be distinguished from those of all other species (except A. ramirezi and A. magnus ) by having a copulatory bulb with well-developed ATA and BTA (fig. 29E–G) and denticles at the base of the Ak; MRk present and Ak extended to the apex (different from A. coylei , A. argenteus , and A. pampa , A. longipalpis , A. cordobensis , A. szumikae ). Cheliceral prolongation without cusps (unlike A. insignis , A. gerschiapelliarum , A. taragui , A. puelche , and A. palmar ).

DESCRIPTION: Holotype male (MACN-Ar 27097, figs. 29A–H): Total length: 15.48. Carapace (fig. 29A): length 5.64, width 5.70. Cephalic region: length 3.18, width 4.44, with two posterior dark triangular markings, posteriorly reaching the fovea; clypeus with 16 bristles and a larger central one, 23 bristles between PME and 8–10 behind each PME-PLE; 6 bristles and a larger one on each side of the OQ. Fovea: length 0.78, width 1.68. Eyes, diameters and interdistances: AME 0.36 (large), ALE 0.40, PME 0.24, PLE 0.24, OQ length 1.20, anterior width 3.16, posterior width 2.72; AME-ALE 0.76, PME-PLE 0.16, AME-PME 0.40, ALE-PLE 0.6, AME-AME 0.20. Chelicerae: Length 3.00, width 1.56 with dorsal internal shallow ridges; numerous small posterior lateral bristles; cheliceral apex with 15 recumbent and elongated bristles that cover the base of the fang. Cheliceral prolongation without cusps; furrow with 6 large promarginal teeth and 5 retromarginal teeth (a small one between 2nd- 3d, 3d-4th and two between 4th-5th) and 16 denticles, near the promarginal teeth. Labium: length 1.32, width 1.08. Maxillae: anterior length 1.56, 2.28 posterior length, width 1.62. Sternum (fig. 29H): With slight central depression; length 4.02, maximum width 3.42, minimum width 1.14. Postlabial sigillum shallow, reaching the center of the sternum; posterior sigilla well defined and shallow. Abdomen: Length 6.00, covered by thin bristles, with 8 spiniform dorsalanterior bristles. PMS: length 0.72; PLS: length of basal:medial:apical segments 0.80:0.28:0.20. Spigots: 1 large, 29 small on PMS; PLS, numbers of large(small) spigots on basal:medial:apical article 3(42):5(40):2(56). Lengths of legs and palp: I: 6.36, 2.52, 3.72, 4.38, 2.52, 19.50. II: 6.30, 2.52, 3.72, 4.80, 2.52, 19.86. III: 5.40, 2.76, 2.88, 4.80, 3.00, 18.84. IV: 7.02, 2.76, 5.40, 5.82, 3.18, 24.18. Palp: 5.88, 2.76, 5.10, –, 1.44, 15.18.

Chaetotaxy: Femora: I-II-IV, 0; III, 1 D A. Patellae: I-II, 0; III, 34 P SUP-D ANT +10 on the margin, 1-1-1-2-1-1 D, 1-2-4 R A +10 on the margin; IV, 47 P SUP-D ANT with 5 near the edge, 1 D B. Tibiae: I, 1-2-3 V POST, 1-1-1 v, 2 V A ANT; II, 1-1-1-2-1-4 R INF, 2-2-2 v, 3 V A POST, 2 V A ANT; III, 1-1 P, 1 D B, with a crown of 18 thorns and 1 apical (at the edge, anterior to the crown), 1 R M, 2-1-3 V; IV, 1-1 P M, 2-3 V (1:2 A). Metatarsi: I, 1-1-1-1-1 V ANT, 1-2-1-1 V, 4-2-2-1-1-2-2-2 V POST-R INF; II, 4-3-1-3-1- 1-3-1-3-4-1-4 R INF-V POST, 1-2-1-1 V, 1-2-1- 1-1-2-V ANT; III, 1-2-1-1-1 D ANT, 1-2-2-1-2-3-2-5 on row D POST-R, 4-2-2-2-1 V, 2-1-2-1-1-1-3-3 V ANT-P INF; IV, 2-2-2-1-2-3-4 P, 1 D A ANT, 1-2-2-3-4 V. Tarsi: I, 1-1-2-1-2 P INF, 32 R INF, 2-0-2-2-3 V; II, 2-2-1-1-2-1-2-4 P INF, 48 R INF, 1-1-1-2-1-2 V; III, 2-2-2-1-1-3-2 P INF, 1-2-1-1-2-2-1 R INF, 1-2 V (1:3 A); IV, 2-2-2-5-3-1-3-1-2-2 P INF, 1-2-3-2-2 R INF. Total number of retrolateral spines on tibiae I and II (fig. 29D): 0 and 10 respectively. A projection in the anterior angle of coxae I. Palp: tibiae long and slender (width/length: 0.30±0.002) (fig. 29C). Bulb robust; ATA and BTA well developed; embolus short with Ak extending to apex with a series of denticles at the base; a MRk present (fig. 29E). Pseudoscopula: Tarsi: I-II, sparse, uniformly distributed throughout the segment, more abundant A; III-IV, dense and uniform. Metatarsi without pseudoscopula. Trichobothria: Tibiae: I 4-4; II 4-7; III 5-8; IV 6-5. Metatarsi: I-II 14; III 12; IV 9. Tarsi: I 12; II 11; III 14; IV 11. Color: Carapace dark reddish brown; cephalic region and chelicerae darker. Abdomen dark brown, booklungs with light markings (fig. 29B). Sternum, labium, and maxillae lighter reddish brown. Spinnerets yellowish. Legs like carapace; palp tibia light.

Paratype female (MACN-Ar 27100, figs. 30A– E): Total length: 25.56. Carapace (fig. 30A): length 9.60, width 9.36; ~38 bristles on each posterior margin. Cephalic region: length 5.64, width 7.20; clypeus with 90 bristles and one central large, chilum small with 40 bristles, 60 between PME and 15 bristles behind each PME-PL; 3–4 between ALE-PLE and 25 on each side of the OQ; two dark triangular markings behind OQ, posteriorly reaching the fovea, and numerous smaller bristles at the back of the cephalic region, more abundant around the fovea. Fovea: wide; length 1.62, width 3.78. Eyes, diameters and interdistances: AME 0.24, ALE 0.30, PME 0.24, PLE 0.30, OQ length 1.32, anterior width 4.32, 4.08 posterior width; AME-ALE 1.50, PME-PLE 0.24, AME-PME 0.84, ALE-PLE 0.72, AME-AME 0.48. Chelicerae: Length 4.50, width 2.76; cheliceral apex with 24 recumbent and elongated bristles covering the base of the fang; dorsal anterior region with shallow ridges. Rastellum with 16 blunt marginal cusps, and 12 small dorsal ones. Fang groove with 6 promarginal teeth and 6 retromarginal ones (on the left chelicera, instead of the second tooth there is a group of 4 denticles; right normal) and 22–25 denticles in the furrow, near the promargin. Labium: length 2.28, width 2.10, with 36 anterior cuspules. Maxillae: anterior length 2.88, posterior length 3.78, width 2.70; +250 cuspules 1:3 V ANT, extending to the anterior face. Sternum (fig. 30E): Slight central depression; length 6.48, maximum width 6.00, minimum width 2.22. Postlabial sigillum shallow, separated from the labium, posterior sigilla shallow and well defined. Abdomen: length 10.44, globose, covered by long bristles, thicker on dorsum. PMS: length 1.00; PLS: length of basal:medial:apical segments 1.40:0.60:0.40. Spigots: 2 large, 40 small on PMS; PLS, numbers of large(small) spigots on basal:medial:apical article 8(58):7(60):3/4(+100). Lengths of legs and palp: I: 4.80, 3.60, 2.40, 3.00, 1.20, 15.00. II: 4.80, 3.60, 2.40, 3.24, 1.20, 15.24. III: 5.16, 4.44, 2.04, 3.60, 1.56, 16.80. IV: 6.72, 4.32, 3.96, 4.20, 1.32, 20.52. Palp: 4.80, 3.36, 3.48, –, 3.60, 15.24.

Chaetotaxy: Femora, 0. Patellae: I-II, 0; III, 10 P SUP +10 on the margin, 25 R A +20 on the margin; IV, 74 P SUP-D ANT +4 near the edge; palp, 1-1- 1 P. Tibiae : I, 1-1-1 P (1:2 A), 26 R (2:3 A), 1-1 V POST M ; II, +150 R, 1-1 V POST; III, 1 D B, with a crown of 26 thorns and 5 apical (at the apex, anterior to the crown), +100 R; IV, 3/1 P A; palp, 9 / 19 P INF, 43 R INF. Metatarsi : I, 30 P INF, 35 R INF, 1-1-2 V POST ; II, 22 P INF, 38 R (more abundant R A), 1-1-2 V POST; III, 22 D ANT, +90 on row D POST-R (more abundant R A), 2 V A; IV, 28 P, 1 D ANT A. Tarsi : I, 11 P INF, 24 R INF, 1 V A ; II, 18 P INF, 17 R INF, 2 V A; III, 40 R, +100 V-P; IV, 43 V-P; palp, 28 P INF, 45 R INF, 1/2 V A. Total number of retrolateral spines on tibiae I and II (fig. 30B): 26 and +150 respectively. Trichobothria: Tibiae: I 4-6 ; II 5-7 ; III 6-8 ; IV 7-8 . Metatarsi : I 13 ; II 18 ; III 15 ; IV 14 . Tarsi: I 10 ; II-III 13; IV 8 . Color: Carapace reddish brown, with mottled darker spots on the back. OQ lighter in the middle ; chilum and clyp- eus with a large light spot (fig. 30A). Chelicerae dark reddish brown with lighter internal dorsal stripes. Abdomen dark brown, booklungs with light markings. Spinnerets yellowish. Sternum light reddish brown, labium and maxillae darker. Legs like carapace .

DISTRIBUTION: Provinces of Chubut, La Pampa, Río Negro, and southern Buenos Aires.

OTHER MATERIAL EXAMINED: Chubut: Península de Valdés, [42°28′ S 63°37′ W], 13 Nov. 1976, P. Domínguez, 5♀ (MACN-Ar 27092). Río Negro. Valcheta [40°50′ S 63°1′ W], Jan. 1945, (name collector illegible), 2♀ (MACN-Ar 27089). Viedma [40°50′ S 63°1′ W], Jan. 2012, H.A. Iuri, 1♀ (MACN-Ar 31206). La Pampa. Conhello [36°0′ S 64°35′ W], Jan. 1939, M.E. Ibañez, 1♂ (MACN-Ar 36584). Santa Rosa [36°38′ S 64°17′ W], no date or collector, 1♂. Buenos Aires: Punta San Blas, Patagones, Escur. Carcelles Daguerre. Oceanográfico “ San Luis ” [40°33′ S 62°15′ W], Mar. 1932, no collector, 1♀ (MACN-Ar 36583). Sierra de la Ventana, Fortín Chaco , undated collection, E. Maury, C. Cesari, and P. Dominguez (MACN-28412). Rio Negro. Balsa de Paso Córdoba (G. Roca), 24 Mar. 1959, no collector 1 ♀ (no spermathecae, MACN- 27090), no data: only identified as A. insignis , 1♀ (MACN-Ar 36586). The specimen with catalog number MACN-27095 (no more data) resembles A. patagonia by the shape of its spermatheca, carapace, and sternum.

COMMENTS: The male and female were matched taking into account the similarities found in the overall size of the specimens, the light booklung markings, the similar form of the sternum, the slight depression in the center of the sternum, and the confluence of the posterior sigilla in the central depression of the sternum.

When Adolfo Doering sent the material of Grammostola doeringi (Holmerg, 1881) to E. Holmberg from the expedition to the Río Negro, as descriptive ecological data he commented the existence of spiders living in “extraordinary abundance on the steppe ... they live in vertical tubes... and carry a lid or mobile door “ ( Holmberg, 1881; Mello-Leitão, 1933). Gerschman de Pikelin and Schiapelli (1962) pointed out that these trapdoors were most likely actinopodids. Based on biogeography, it is very likely that the observed specimens were representatives of A. patagonia .