Ctenus serratipes F.O. Pickard-Cambridge, 1897

Polotow, Daniele & Brescovit, Antonio D., 2012, Redescription of five Amazonian species of Ctenus Walckenaer (Araneae, Ctenidae, Cteninae), Zootaxa 3338, pp. 49-59 : 54-56

Ctenus serratipes F.O. Pickard-Cambridge, 1897

Figs 4 A–D, 5A–C

Ctenus serratipes F.O. Pickard-Cambridge, 1897: 87 , pl. 3, figs VI.c and VII.d ( male holotype from Demerara, 6° 48'N, 58° 10'W, Demerara-Mahaica region, Guyana, deposited in BMNH, examined ).

Ctenus fulvipes Caporiacco, 1947: 27 (male holotype from Great Falls, Demerara, 6° 48'N, 58° 10'W, Guyana, X.1931, Beccari & Romiti col., deposited in MZS, examined); Caporiacco 1948: 679, figs 98 – 99. New synonymy.

Ctenus scenicus Caporiacco, 1947: 28 (penultimate instar female syntype from Essequibo River, 6° 31'N, 58° 19'W, Essequibo Islands, West Demerara Region, Guyana and penultimate instar female syntype from Potaro River, Guyana, Beccari & Romiti col., deposited in MZS, examined); Caporiacco 1948: 680, fig. 100. New synonymy.

Ctenus itatiayaeformis Caporiacco, 1955: 394 (penultimate instar female holotype from Caracas, 10° 30'N, 66° 55'W, Venezuela, 15.I.1950, Foldats col., deposited in MUCV 806, examined). New synonymy.

Diagnosis. Males of Ctenus serratipes resemble those of C. paubrasil ( Brescovit & Simó 2007: figs 31–32) by the shape of the laminar basal projection of the embolus, but can be distinguished by the thin retrolateral tibial apophysis, absence of tegular projection ( Figs 4 A–B) and metatarsus IV modified ( Figs 5 A–C). Females resemble those of Ctenus paubrasil ( Brescovit & Simó 2007: figs 33–34) by the elongated anterior area of the epigynal median sector, but can be distinguished by the larger epigynal ovoid lobes and the shape of the lateral sector processes ( Fig. 4 C).

Description. Male (MPEG 9007). Colouration: Carapace reddish brown, pars thoracica pale brown, thoracic groove dark brown; black rings around eyes; legs reddish brown, with ventral face of coxae and femora lighter; chelicerae reddish brown; endites and labium reddish brown, lighter at tips; sternum reddish brown; abdomen gray with several small black spots, covered with long hairs, with dorsal anterior light area and three pairs of black spots in dorsal median area; ventral abdomen with V-shaped darker area, from epigastric furrow to spinnerets, with two white spots near epigastric furrow. Total length 14.10. Carapace 7.80 long and 6.00 wide. Clypeus 0.44 high. Eye diameters: AME 0.47, ALE 0.26, PME 0.51, PLE 0.51. Chelicerae with 3 promarginal teeth, median larger; 4 retromarginal teeth, basal small; with intermarginal denticles. Leg measurements: I: femur 8.60/ patella 3.50/ tibia 8.90/ metatarsus 7.90/ tarsus 2.90/ total 31.80; II: 8.50/ 3.50/ 8.60/ 7.70/ 2.60/ 30.90; III: 7.00/ 2.90/ 5.90/ 6.50/ 2.30/ 24.60; IV: 8.90/ 3.10/ 8.50/ 9.40/ 3.90/ 33.80. Leg formula 4123. Leg spination: tibia I and II v2-2 -2-2-2, r1-1-0, p1-1-1-0, III and IV v2-2 -2, r1-1-0, p1-1-0; metatarsus I, II v2-2 -2, r1-1-0, p-1-1-0, III v2-2 -2, r1-1-1, p1-1-1; metatarsus IV modified ( Figs 5 A–C). Palp: tibiae as long as cymbium; short retrolateral tibial apophysis on apical margin of tibia; RTA laminar, indented at tip; cymbium elongated, without basal projections; tegulum without projections; embolus with broad base, large tip, with laminar basal projection; median apophysis cup-shaped, bimarginated and short; conductor hyaline, C-shaped in retrolateral view ( Figs 4 A–B).

Female (MPEG 9008). Colouration as in male. Total length 15.60. Carapace 7.80 long and 6.10 wide. Clypeus 0.38. Eye diameters: AME 0.35, ALE 0.28, PME 0.37, PLE 0.35. Chelicerae with 3 promarginal teeth, median larger; 4 retromarginal teeth, basal small; with intermarginal denticles. Leg measurements: I: femur 6.80/ patella 3.40/ tibia 6.40/ metatarsus 5.80/ tarsus 1.80/ total 24.20; II: 6.80/ 3.30/ 6.10/ 5.60/ 1.80/ 23.60; III: 5.70/ 2.70/ 4.50/ 5.20/ 1.80/ 19.90; IV: 7.10/ 2.70/ 6.40/ 8.40/ 2.60/ 27.20. Leg formula 4123. Leg spination: tibia I and II v2- 2 -2-2-2, r0, p0, III and IV v2-2 -2, r1-1, p1-1; metatarsus I, II v2-2 -2, r0, p0, III v2-2 -2, r1-1, p1-1, IV v1-1 -1-2-2, r1-1, p1-1. Epigynum: median sector subrectangular; with two ovoid lobes positioned longitudinally; median sector with swollen posterior area; ovoid lobes elongated; lateral spurs originating closer to the apex of the lateral sector ( Fig. 4 C); spermathecae oval, with two small prolateral projections; copulatory ducts, long, large and narrow; fertilization duct short, originating from retrolateral side of spermathecae ( Fig. 4 D).

Variation. 10 males: total length 14.1019.70; carapace 7.80–9.70 long; femur I 8.60– 10.30. 10 females: total length 15.60–20.20; carapace 7.80–11.30 long; femur I 6.80–9.30.

Additional material examined. BRAZIL. Pará: Juruti (2° 23' 60”S 56° 17' 60”W), 3 males and 19 females ( MPEG 13919 , 13924, 13929, 13932, 13933, 13937, 13964, 13975, 13989, 14009); ( Comunidade Café Torrado , 2° 23' 60”S 56° 17' 60”W), 1 female ( MPEG 13934 ); ( Acampamento Mutum , 0 2o 36'11.2" S 56o12'36.3"W), 1 female ( MPEG 8647 ); (Acampamento Barroso, 0 2o 28'10.5"S 56o00'3.5"W), 1 female ( MPEG 8645 ); (02o28'22.1"S 56o12'29.4"W), 1 female ( MPEG 13960 ); (02o28'22.1"S 56o12'29.4"W), 1 female ( MPEG 13938 ); (Ramal Pacoval, Km 2, 0 2o 28'0.6"S 56o12'42.2"W), 1 male ( MPEG 13949 , 13998, 14003); ( Sítio Três Irmãos , 0 2o 27'51.4"S 56o00'08.6"W), 2 males and 5 females ( MPEG 9007 , 9008, 13939, 13954, 13963, 14006); ( Platô Carapiranga , 0 2o 28'22.1"S 56o12'29.4"W), 6 females ( MPEG 8506 , 9100, 13930, 13955, 13958, 13961); ( Sítio Barroso , 0 2o 27'41.7"S 56o00'11.6"W), 2 males ( MPEG 8643 , 8646); (Vale do Igarapé Mutum, Platô do Rio Juruti, 0 1o 36'44.7"S 56o11'39.2"W), 2 males and 3 females ( MPEG 8481 , 8650, 9006, 9015, 13994) .

Distribution. North of Guyana and north of the State of Pará, Brazil ( Fig. 7 ).

Figures

FIGURE 4. Ctenus serratipes (male MPEG 9007 and female MPEG 9008). Male genitalia. A. Male palp, ventral view; B. Male palp, retrolateral view. Scale bar: 2.00 mm. Female genitalia. C. Epigynum, ventral view; D. Vulva, dorsal view. Scale bar: 0.50 mm. Abbreviations: C, conductor; CD, copulatory ducts; CY, cymbium; E, embolus; FD, fertilization ducts; LBP, laminar basal projection of the embolus; LL, lateral lobes; LS, lateral sectors; MA, median apophysis; MS, median sector; OL, ovoid lobes; TE, tegulum; TI, tibia.

FIGURE 5. Ctenus serratipes (MPEG 9007), left metatarsus IV. A. dorsal view; B. retrolateral view; C. prolateral view.

FIGURE 7. Collection localities of five Ctenus species. A. South America; B. Close up, northeastern South America. Legend: square = C. delesserti; black circle = C. falconensis and C. sigma; gray circle = C. nigritus; triangle = C. serratipes.