Afroceto gracilis, Lyle & Haddad, 2010

Lyle, Robin & Haddad, Charles R., 2010, A revision of the tracheline sac spider genus Cetonana Strand, 1929 in the Afrotropical Region, with descriptions of two new genera (Araneae Corinnidae), African Invertebrates 51 (2), pp. 321-321 : 357-359

Afroceto gracilis sp. n.

Figs 15 , 77–79

Etymology: From Latin gracilis (slender); refers to the slender embolus of the male.

Diagnosis:The male can easily be recognised by the slender, pointed embolus, which runs prolaterally of the tegulum at its base and obliquely towards the retrolateral margin in its distal section ( Fig. 78 ). The tegular sperm duct has two sharp bends, one proximal and the second retrolateral ( Fig. 78 ). The retrolateral tibial apophysis is short and triangular, with a broad base and dorsally directed rounded tip ( Fig. 79 ). Female unknown.

Description:

Male.

Measurements: CL 1.50–2.23, CW 1.15–1.65, AL 1.81–2.56, AW 0.96–1.56, TL 3.69– 5.04, FL 0.10–0.23, SL 0.88–1.19, SW 0.80–1.00, AME–AME 0.08, AME–ALE 0.02, ALE–ALE 0.37, PME–PME 0.14, PME–PLE 0.10, PLE–PLE 0.59. Length of leg segments (sequence from femur to tarsus, and total): I 1.90+0.88+1.47+1.20+0.84=6.29; II 1.67+0.78+1.31+1.14+0.80=5.70; III 1.20+0.63+0.88+1.06+0.51=4.28; IV 1.78+0.73+ 1.49+1.75+0.64=6.39.

Carapace brown to dark brown nearing borders ( Fig. 15 ); highest point in first third of carapace; gradually decline until last quarter, last quarter with steep decline; surface finely granulate, covered in short, fine setae; fovea distinct, at two thirds carapace length. Ocular region brown, with dark brown rings around eyes; AER recurved, AME slightly larger than ALE; clypeus height subequal to AME diameter; AME separated by distance equal to approximately half their diameter; AME separated from ALE by 0.33 AME diameter; PER slightly recurved, PME slightly larger than PLE; PME separated by distance slightly larger than their diameter; PME separated from PLE by distance slightly less than PME diameter. Chelicerae brown, darker towards fang base; long, fine setae scattered on anterior surface, slightly longer towards fang base; fangs orange, darker towards fang base; three promarginal teeth, median tooth largest, distal tooth smallest; two retromarginal teeth, distal tooth largest. Sternum pale orange, brown towards border; surface covered in short fine setae. Abdomen pale yellow to orange dorsally, with grey stripe laterally, extending to half abdomen length; abdomen broader anteriorly, tapering posteriorly; abdomen with brown scutum covering almost entire dorsum; two pairs of pale brown, indistinct sigilla. Legs I to IV yellow to light brown, dense ventral setae on tibiae, metatarsi and tarsi; anterior legs more robust than posteriors; femora with large incomplete band covering almost entire segment, patellae with incomplete dorsal band, tibiae and metatarsi with two incomplete bands, situated proximally and distally; leg spines and cusps present. Leg spination: femora: I pl 2, II pl 1, III pl 1; patellae spineless; tibiae: I plv 7–8 rlv 3 vt 2 cusps, II plv 4–5 cusps, III pl 1 plv 1 vt 2, IV vt 2; metatarsi: I plv 10–12 rlv 7–8 vt 1–2 cusps, II plv 8–9 rlv 3–4 vt 1–2 cusps, III pl 1 rl 1 plv 1, IV pl 1 rl 1 plv 1 rlv 1 vt 2; tarsi: I plv 4–5 rlv 4 cusps, II plv 4–5 rlv 3–4 cusps ( Fig. 77 ). Palp brown, tegulum elongate; embolus originating prolaterally, curving retrolaterally toward cymbium tip, distal section slender and pointed; sperm duct with sharp proximal and retrolateral bends ( Fig. 78 ); retrolateral tibial apophysis short and triangular, with broad base, tip rounded and directed dorsally ( Fig. 79 ).

Holotype: ♂ SOUTH AFRICA: Mpumalanga: Dullstroom, Sakhelwe Location , 25°24.887'S: 30°05.572'E, 2017 m, 26–29 xi.2008, L. Makaka, pitfall traps ( NCA, 2009/4819).

Paratypes: SOUTH AFRICA: Mpumalanga: 1♂ Dullstroom, Groblers Farm , 25°20.002'S: 30°06.292'E, 1950 m, 26–29 xi.2008, L. Makaka, pitfall traps ( NCA, 2009/4817) ; 1♂ Dullstroom, Verloren Vallei Nat. Res. , 25°18.832'S: 30°07.791'E, 2189 m, 26–29 xi.2008, L. Makaka, pitfall traps ( NCA, 2009/4818) ; 1♂ Veloren Vallei Nat. Res., Block 3, 25°18.832'S: 30°07.791'E, 29.xi–2 xii.2008, L. Makaka, pitfall traps ( NCA, 2010/226) ; 1♂ Roger Croall , 25°32'S: 30°04'E, 26–29 xi.2008, L. Makaka, pitfall traps ( NCA, 2010/223) .

Distribution: Known only from the Dullstroom district in Mpumulanga Province, South Africa ( Fig. 80 ).

Figures

Figs 1–22. General appearance of Afroceto gen. n. species: A. martini (Simon, 1897) comb. n. female (1) and male (2); A. arca sp. n. female (3) and male (4); A. bulla sp. n. female (5); A. bisulca male (6); A. capensis sp. n. female (7) and male (8); A. coenosa (Simon, 1897) comb. n. female (9); A. corcula sp. n. female (10); A. croeseri sp. n. female (11) and male (12); A. flabella sp. n. male (13) and female (14); A. gracilis sp. n. male (15); A. plana sp. n. male (16) and female (17); A. porrecta sp. n. male (18); A. rotunda sp. n. male (19) and female (20); A. spicula sp. n. male (21) and female (22).

Figs 77–79. Afroceto gracilis sp. n. male: (77) schematic representation of cusp arrangement on legs I and II; (78) left palp, ventral view; (79) left palp, retrolateral view. Scale bar (78, 79) = 0.1 mm.

Fig. 80. Distribution of Afroceto croeseri sp. n., A. flabella sp. n. and A. gracilis sp. n. in South Africa.