Actinopus longipalpis Koch, 1842

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 : 49-52

Actinopus longipalpis Koch, 1842

Figures 23A–I, 24A–D, 44

Koch, 1842: 102, fig. 754.

TYPE MATERIAL: HOLOTYPE ♂ ( ZMB 2107 ) from Uruguay: Montevideo [34°52′ S 56°10′ W]: C.L. Koch, 1842, examined.

DIAGNOSIS: Females of A. longipalpis differ from all other species by the shape of their spermathecae (fig. 24D); wide basally, with welltruncated fundus, concave dorsally with external lobes projected perpendicular to the duct (similar to A. argenteus , A. casuhati , and A. gerschiapelliarum ). They differ from A. argenteus and A. casuhati by the smaller number of retrolateral spines on tibia II; and from A. gerschiapelliarum by the form and shape of their spermathecae. Males can be differentiated from all other species by a copulatory bulb rounded with a tapering embolus (fig. 23G–I), and a low number of retrolateral spines on tibiae II (fig. 23F). They differ from A. pampa and A. argenteus by the abdomen with a brown dorsum.

REDESCRIPTION: Male (ZMB 2107; figs. 23A–I): Total length: ~15.04 (abdomen shrunk). Carapace (fig. 23A): length 6.586, width 6.48. Cephalic region: length 3.94, width 4.88; clypeus small. Fovea: length 0.94, width 2.06. Eyes, diameters and interdistances: AME 0.24 (large), ALE 0.48, PME 0.24, PLE 0.28, OQ length 1.24, anterior width 3.07, 2.83 posterior width; AME-ALE 0.67, PME-PLE 0.24, AME-PME 0.38, ALE-PLE 0.62, AME-AME 0.33. Chelicerae: Length 2.53, width 1.88; cheliceral apex with 12 recumbent and elongated bristles that cover the base of the fang. Cheliceral prolongation without cusps (fig. 23D); cheliceral furrow with 7 large promarginal teeth and 5 retromarginal ones (a small one between 3d–4th and 4th–5th) and 10 denticles, near the promarginal teeth. Labium: length 1.41, width 1.50. Maxillae: anterior length 2.06, posterior length 2.82, width 2.06. Sternum: Center with slight depression (fig. 23B): length 4.32, maximum width 3.76, minimum width 1.50. Postlabial sigillum shallow, reaching the center; posterior sigilla well defined. Abdomen (compressed, fig. 23C): length ~4.70. Lengths of legs and palp: I: 5.92, 2.82, 3.29, 4.23, 2.06, 18.32. II: 5.64, 2.63, 3.10, 4.51, 2.16, 18.04. III: 5.17, 2.91, 2.63, 5.26, 2.93, 18.90. IV: 6.39, 3.19, 4.98, 5.80, 3.00, 23.36. Palp: 5.82, 2.91, 4.88, –, 1.59, 15.20.

Chaetotaxy: All legs with numerous elongated bristles. Femora: I-IV, 0. Patellae: I-II: 0; III, 30 P SUP-D ANT +8 on the margin, 1-1-1 D (1:2B), 6 R A (on the margin); IV, 34 P SUP-D ANT. Tibia: I, 0; II, 1-1-1 R INF; III, 1-2-1 R (1:2A), 1-1 P, with an apical crown of 16 thorns; IV, 1-2-3 P, 1-1-2-3- 3-2 v. Metatarsi: I, 1-1 P INF, 1-1-1 R INF; II, 1-1-1 P INF (1:3 A), 1 R A; III, 1-1-2-2-2 P, 1-1-2 R INF, 1-1 R SUP; IV, 1-1-1-2-1-2-3 P, 3-2-2-3-2- 3-1-2 V. Tarsi: I, 1-1-1-1-1-1 P INF (3:4 A), 1-1-2 R INF; II, 1-1-1-1-1-1 P INF, 1-2-2-2 R INF; III, 1-1-2-1-1-1-1 P INF, 1 R INF (1:2 A); IV, 1-3-1-4- 2-2-1 P INF. Total number of retrolateral spines on tibiae I and II (fig. 23F): 0 and 3 respectively. Palp: tibiae long and slender (width/length: 0.29±0.01) (fig. 23E). Bulb (fig. 23G–I) with ATA developed, BTA little developed. Pseudoscopula: Tarsi: I–II, sparse apical; III–IV, dense and uniform. Trichobothria: Tibiae: I 5-4; II 4-5; III 5-6; IV 6-6. Metatarsi: I 10; II 9; III–IV 10 Tarsi: I-II- III 9; IV 10. Color: Carapace and chelicerae dark. Abdomen dark brown. Booklungs with dark markings. Legs like carapace with lighter tibiaemetatarsi-tarsi; palp with lighter tibiae.

Female (MNHN 308, figs. 24A–D): Total length: 13.32. Carapace (fig. 24A): length 4.68, width 4.44; with 15 bristles on each posterior margin. Cephalic region: length 2.76, width 3.96; clypeus small with 12 bristles, 6 on chilum; 2 bristles between AME- ALE, 10 bristles between PME and 4 behind each PME-PLE, 11 bristles and one larger on both sides of the ocular group. Fovea: length 0.72, width 2.16. Eyes, diameters and interdistances: AME 0.08, ALE 0.32, PME 0.20, PLE 0.28, OQ 1.00, anterior width 2.44, 2.28 posterior width; AME-ALE 0.76, PME- PLE 0.12, AME-PME 0.48, ALE-PLE 0.52, AME- AME 0.20. Chelicerae: Length 2.34, width 1.74, chelicerae apex with 18 recumbent and elongated bristles covering the base of the fang. Rastellum with 8 marginal, blunt cusps and 9 small dorsal small. Fang groove with 7 promarginal and 5 retromarginal teeth (a small tooth between 3d–4th and 4th–5th) and 6 denticles in the furrow, near the promargin. Labium: length 0.72, width 0.90, with 9 anterior cuspules. Maxillae: anterior length 1.32, posterior length 1.80, width 1.20, with +70 cuspules 1:3 V ANT, expanding to the anterior face. Sternum: Center flat (fig. 24B), length: 4.02, maximum wide 2.70, minimum width 0.90. Postlabial sigillum deep, posterior sigilla shallow and well defined. Abdomen: length 6.36, covered by dark bristles. Posterior median spinnerets: length 0.60; posterior lateral spinnerets with basal:medial article 0.80:0.36 (apical segment compressed). Spigots: 2/3 large, 20 small on PMS; PLS, numbers of large(small) spigots on basal:medial:apical article 4/2(20):3(22):(~30). Lengths of legs and palp: I: 2.52, 1.80, 1.20, 1.50, 0.78, 7.80. II: 2.52, 1.62, 1.20, 1.50, 0.78, 7.62. III: 2.40, 1.80, 0.90, 1.62, 0.66, 7.38. IV: 3.00, 1.80, 1.80, 1.92, 0.66, 9.18. Palp: 2.52, 1.50, 1.80, –, 1.80, 7.62.

Chaetotaxy: All femora: 0. Patellae: I-II, 0; III, 6 P A +7 on the margin, 11 R A +10 on the margin; IV, 42 P SUP-D ANT; palp, 0. Tibiae: I, 1-1 V POST; II, 45 R, 1-1 v post; III, 1 D B, with a apical crown of 20 thorns, 32 R; IV, 0; palp, 7 P INF (serials), 5 R INF (serials). Metatarsi: I, 13 P INF, 1-2-1-2 V POST; II, 1-2-1-3 P INF, 1-1-1-2 V POST; III, 1-1-2-1-1-1-3 D ANT-P SUP, 24 on row D POST-R (more abundant R A); IV, 1-2-3 P INF, 1 D A. Tarsi: I, 8 P INF (serial), 1-1-2-3-2 R INF, 2 V A; II, 2-2-2-1-1-1 P INF, 1-1-5 R INF, 2 V A; III, 8 R, 27 V-P; IV, 32 V-P; palp, 13 P (serial), 11 R INF (serial), 2 V A. Total number of retrolateral spines on tibiae I and II (fig. 24C): 0 and 45 respectively. Trichobothria: Tibiae: I 4-5; II 5-5; III-IV 5-6. Metatarsi: I 9; II 10; III 7; IV 6. Tarsi: I 8; II-III 7; IV 5. Color: Carapace yellowish brown; cephalic region and chelicerae darker. Abdomen light brown; booklungs with light markings. Sternum light yellowish, labium and maxillae darker. Spinnerets yellowish. Legs like carapace.

DISTRIBUTION: Northern and southern Uruguay and northern Argentina (Entre Ríos province).

OTHER MATERIAL EXAMINED: URUGUAY. Artigas. Arroyo Tres Cruces [30°16′ S 57°11′ W], leg. Robayna D., 1♂, 15 Feb.1965, ( MNHN 621 ) ; Arroyo Tamanduá [30°28′ S 56°33′ W], leg. de Zolessi L.C and Gonzalez-Olazar, 1♀, 20 May. 1872, ( MNHN 308 ). ARGENTINA: Entre Ríos: Rosario del Tala [32°18′ S 59°8′ W], leg. Buero, 1♂, no date, (MACN-Ar. 27099) ; San José, [32° 12′ S 58° 13′ W], A. Oliva, 1♂, Jan. 1989, (MACN-Ar 27096) .

COMMENTS: None of the specimens from the vicinity of Montevideo examined by the senior author belong to A. longipalpis . Although the type locality of A. longipalpis is “ Montevideo,” it seems likely that Montevideo was simply the shipping port for the specimen.