Tapinauchenius rasti Hüsser, 2018

Cifuentes, Yeimy & Bertani, Rogerio, 2022, Taxonomic revision and cladistic analysis of the tarantula genera Tapinauchenius Ausserer, 1871, Psalmopoeus Pocock, 1985, and Amazonius n. gen. (Theraphosidae, Psalmopoeinae), Zootaxa 5101 (1), pp. 1-123 : 54-57

Tapinauchenius rasti Hüsser, 2018

( Figs 19 , 21–22 , 111–118 , 120–121 )

Tapinauchenius rasti Hüsser, 2018: 81 , figs 10A–B, 11A–C, 12A–C.

Diagnosis. Females of Tapinauchenius rasti resemble those of T. plumipes , T. cupreus , T. latipes and T. polybotes in having spermathecae with a constriction near the tip, forming a small and strongly sclerotized lobe ( Fig. 118 ). They differ from those of T. plumipes by the tibiae III tip lacking an apical-ventral row of spiniform setae; and legs, carapace and chelicerae lacking a violet sheen. They differ from females of T. latipes by the longer spermathecae; from T. cupreus by the non-oval spermathecae shape, and from T. polybotes by the geographic distribution on Union Island, in the Caribbean ( Figs 21–22 ). Males of T. rasti resemble those of T. polybotes by the short embolus less than 2.7 times subtegulum length ( Fig. 111 ). They differ from T. polybotes by the embolus tip lacking a sinuous curvature in dorsal view ( Fig. 114 ).

Type material. Holotype male and paratype female from Union Island , St. Vincent and the Grenadines, Lesser Antilles, Burgess leg., B. Rast ded., 2013, deposited at SMF, not examined.

Other material examined. SAINT VINCENT AND THE GRENADINES: Union Island [12°35’53”N, 61°26’15”W], near Monte Tabor, 3 males, R. Powell col. from silken retreat in tree cavities, 16 June 2010 ( MZUSP 76533 ); 1 female, same data and collector ( MNRJ 7702 ); Mustique island [12°52’N, 61°11’W] near Barbados, 1 male, BZ Raphael DVM col., 1991, identified as T. plumipes (AMNH-Tap-1.)

Redescription. Male (MZUSP 76533). Total length, not including chelicerae or spinnerets 29.62. Carapace 13.09 long, 11.97 wide, 2.88 high. Chelicera: 6.39 long. Legs (femur, patella, tibia, metatarsus, tarsus, total): I: 12.47, 7.11, 11.05, 10.52, 5.02, 46.17; II: 11.10, 6.49, 9.72, 10.03, 4.56, 41.90; III: 9.66, 5.38, 10.72, 9.37, 4.80, 39.93; IV: 11.58, 5.65, 10.89, 12.10, 4.77, 44.99; Palp: 7.93, 4.33, 6.85, -, 2.58, 21.69. Midwidths: femora I–IV= 2.74, 2.55, 2.71, 2.64, palp= 1.94; patellae I–IV= 2.59, 2.45, 2.50, 2.46, palp= 2.03; tibiae I–IV= 2.17, 1.93, 1.98, 1.97, palp= 2.00; metatarsi I–IV= 1.31, 1.22, 1.15, 1.20; tarsi I–IV= 1.16, 1.23, 1.33, 1.30, palp= 1.97. Abdomen: 16.53 long, 9.98 wide. Spinnerets: PMS, 1.97 long, 0.61 wide, 0.79 apart; PLS, 3.01 basal, 2.11 middle, 3.16 distal; midwidths 1.16, 0.84, 0.57, respectively. Carapace: 1.09 times longer than wide; cephalic region slightly raised, thoracic striae conspicuous. Fovea: deep, straight, 1.20 wide. Eyes: eye tubercle 0.49 high, 1.69 long, 2.85 wide. Clypeus: absent. Anterior eye row straight, posterior recurved. Eye size and interdistances: AME 0.67, ALE 0.65, PME 0.42, PLE 0.52, AME–AME 0.36, AME–ALE 0.22, AME–PME 0.26, ALE–ALE 2.04, ALE–PME 0.35, PME–PME 1.54, PME–PLE 0.13, PLE–PLE 2.17, ALE–PLE 0.27. Maxilla: length to width 1.73. Cuspules: ca. 179 spread over ventral inner heel. Labium: 2.08 long, 2.40 wide, with ca. 157 cuspules spaced by one diameter from each other on anterior third. Chelicera: basal segment with 9 teeth in row. Sternum: 6.37 long, 5.12 wide.

Legs: Formula: I = IV II III. Length leg IV to leg I: 0.97. Scopula: Tarsi I–IV fully scopulate; IV with few sparse setae. Metatarsi I–II fully scopulate; III 2/3 distal; IV 1/2 distal. IV divided by rows of setae. Spination: Palps and legs (ventral apical: tibia/metatarsi): Palp 0; I: 1 behind retrolateral process of tibial apophysis; II: 2/0; III 1/0; IV 0/0. Tibial apophysis ( Figs 115–117 ): two processes, retrolateral longer than prolateral, one spine at side of prolateral process, one on apical part of retrolateral process. Conspicuous triangular protuberance behind retrolateral process. Metatarsus I folds on retrolateral side of tibial apophysis.

Palp ( Figs 111–114 ): tegulum length 1.28, width 1.40, embolus proximal width 0.62, length 3.08. Embolus proximal portion roughly straight. Embolus length to tegulum length: 2.40, thick proximal embolus and straight tip. Embolus distal portion narrows abruptly ending in a curved tip.

Color pattern (preserved in alcohol): Carapace, legs, palpal femora, and tibiae brown-reddish; abdomen light brown.

Redescription. Female (MNRJ 7702). Total length, not including chelicerae or spinnerets 39.32. Carapace 18.3 long, 16.13 wide, 5.08 high. Chelicera: 10.32 long. Legs (femur, patella, tibia, metatarsus, tarsus, total): I: 14.29, 9.25, 11.01, 10.66, 5.20, 50.41; II: 12.78, 8.42, 10.16, 10.20, 4.49, 46.05; III: 11.16, 7.00, 8.64, 9.76, 4.68, 41.24; IV: 13.56, 7.66, 11.50, 12.53, 4.65, 49.9; Palp: 10.08, 5.94, 6.79, -, 6.75, 29.56. Midwidths: femora I–IV= 3.44, 3.55, 3.6, 3.59, palp= 2.91; patellae I–IV= 3.94, 3.72, 3.43, 3.46, palp=3.18; tibiae I–IV= 3.13, 2.80, 2.84, 2.98, palp= 2.70; metatarsi I–IV= 2.46, 2.12, 1.80, 1.77; tarsi I–IV= 2.36, 2.21, 2.29, 2.07, palp= 2.46. Abdomen: 21.02 long, 12.55 wide. Spinnerets: PMS, 2.29 long, 1.01 wide, 0.45 apart; PLS, 3.38 basal, 2.66 middle, 3.80 distal; midwidths 1.64, 1.33, 1.16, respectively. Carapace: 1.13 times longer than wide; cephalic region slightly raised, thoracic striae conspicuous. Fovea: deep, straight, 2.13 wide. Eyes: eye tubercle 0.34 high, 2.01 long, 3.65 wide. Clypeus: absent. Anterior eye row straight, posterior slightly recurved. Eye size and interdistances: AME 0.74, ALE 0.75, PME 0.38, PLE 0.60, AME–AME 0.52, AME–ALE 0.54, AME–PME 0.40, ALE–ALE 2.69, ALE–PME 0.61, PME–PME 1.99, PME–PLE 0.21, PLE–PLE 3.02, ALE–PLE 0.30. Maxilla: length to width 1.38. Cuspules: ca. 198 spread over ventral inner heel. Labium: 2.56 long, 3.72 wide, with ca. 150 cuspules spaced by one diameter from each other on anterior third. Chelicera: basal segment with 12 teeth in row. Sternum: 9.26 long, 7.40 wide.

Legs: Formula: I = IV II III. Length leg IV to leg I: 0.98. Scopula: Tarsi I–IV fully scopulate; IV with few sparse setae. Metatarsi I–II fully scopulate; III 3/4 distal; IV 1/2 distal. IV divided by rows of setae. Spination: Palps and legs (ventral apical: tibia/metatarsi): Palp 1 prolateral, 1 apical; I: 1/0; II 2/0; III 1/ 0; IV 1/0.

Spermathecae ( Fig. 118 ): Two spermathecae completely separated, long and triangular, with an apical wellsclerotized lobe.

Color pattern (preserved in alcohol): Carapace, chelicerae, legs, palps and tibiae brown, covered with light brown setae. Abdomen dark brown. Maxillae, labium, sternum and half part of coxae black.

Distribution. Saint Vincent and the Grenadines ( Figs 21–22 ).

Remarks. Two ( T. rasti , T. polybotes ) to three ( T. sanctivincenti ) species seem to be endemic to some of the Windward Islands in the Caribbean. A male from Mustique Island we examined resembles those of T. rasti but has shorter embolus with stouter base. That’s the only species in the Archipelago to occur in two islands ( Fig. 22 ); or, it can be an undescribed species. As we have a single specimen with only this slight morphological difference, it is not possible to answer this question. By the way, the region shows an interesting island endemism and other neighbor islands should be searched for Tapinauchenius specimens. This is of particular interest to those studying evolution in islands and biogeography.

Figures

FIGURE 19. Single cladogram obtained with setk.run and concavity 10.239258 (continued), showing the resolution of Psalmopoeinae clade. Absolute and relative Bremer support are in each node.

FIGURES 21–23. 21, Map showing geographic records (dots) of Tapinauchenius species. 22, detail of the geographic records (dots) of T. sanctivincenti, T. latipes, T. polybotes and T. rasti. 23, detail of the geographic records (dots) of T. plumipes (red) and T. gretae n. sp. (black) in Central Amazonia, Brazil. Tapinauchenius plumipes (red), T. sanctivincenti (pink), T. latipes (green), T. brunneus (brown), T. cupreus (yellow), T. polybotes (purple), T. rasti (light blue), T. gretae n. sp. (black). MI = Mustique island; SL = Saint Lucia island; SV = Saint Vincent island; UI = Union island; TR = Trinidad; VE = Venezuela.

FIGURES 111–118. Tapinauchenius rasti. (111–117) male (MZUSP 76533). (111–114) left bulb (mirrored). 111, retrolateral. 112, prolateral. 113, frontal. 114, dorsal. (115–117) left leg I tibial apophysis. 115, ventral. 116, prolateral. 117, retrolateral. (118) female (MNRJ 7702), spermathecae. Scale bars = 1 mm.

FIGURES 119–121. 119, Tapinauchenius polybotes, living female from Saint Lucia Island. (120–121), Tapinauchenius rasti, 120, female from Union Island, Mount Tabor. 121, male from same locality. Photos: Rick C. West.