Isoctenus cabula, Pontes Moraes & Polotow & Labarque & Da Silva, 2023

Pontes Moraes, Isadora M., Polotow, Daniele, Labarque, Facundo M. & Da Silva, Marcio B., 2023, Description of three new species of Isoctenus Bertkau, 1880 and new records for I. areia Polotow & Brescovit (Araneae, Ctenidae) from northeastern Brazil, Zootaxa 5315 (2), pp. 177-186 : 181-183

Isoctenus cabula new species

Figures 3 , 4 , 7

Type material. Male holotype from Campus 19º Batalhão Caçadores, Cabula, Salvador, 12º57’S, 38º27’W, Bahia, Brazil, 6–11.VI.2007, D. Uzel coll., deposited in IBSP 135436. Female paratype from the same locality and data, deposited in IBSP 135435 .

Additional material examined. BRAZIL. Bahia: Lauro de Freitas , 12º53’S, 38º18’W, 1male, 4.X.1989.(UFBA-LAP 545); 1 male, 1.VII.1990 (UFBA-LAP 694); Itapuã, Lagoa Abaeté, 12º58’S, 38º30’W, 1 male, 4.V.1991, L.L. Casais coll. (UFBA-LAP 873); Salvador, Cabula, Campus 19º Batalhão Caçadores, 12º57’S, 38º27’W, 1 male and 3 females, 6–11.VI.2007, D. Uzel coll. (IBSP 135385; 135437); Salvador, Ondina, Parque Zoobotânico , 13º00’S, 38º30’W, 1 male, 26.XI.1993, M.F. Dias coll. (UFBA-LAP 1388) .

Etymology. The species name is a toponym in apposition referring to the type locality.

Diagnosis. Males of Isoctenus cabula new species resemble those of I. foliifer Bertkau, 1880 by the shape of the RTA, but can be distinguished by a slightly longer tip of the dorsal branch of the RTA, a well-developed and pointed apically ventral retrolateral projection of the cymbium, and an elongated posterior projection of the median apophysis ( Fig. 4A–B ), whereas I. foliifer can be distinguished by a slightly shorter tip of the dorsal branch of the RTA, a poorly-developed and blunted apically ventral retrolateral projection of the cymbium, and a shorter posterior projection of the median apophysis ( Polotow & Brescovit 2009: fig. 4A–B). Females of Isoctenus cabula new species resemble those of I. foliifer by the cordiform-shaped median field of the epigynum, but can be distinguished by a slightly shorter median field of the epigynum and smaller lateral spurs ( Fig. 4C ), whereas I. follifer can be distinguished by a slightly longer median field of the epigynum and larger lateral spurs ( Polotow & Brescovit 2009: fig. 4C).

Description. Male (holotype, IBSP 135436). Prosoma reddish brown, with diverging dark stripes from the thoracic groove to the margin of the carapace; carapace with light brown border; brown thoracic groove and black rings around eyes ( Fig. 3A ). Sternum, endites, labium, and legs light reddish brown ( Fig. 3B ). Brownish dorsum of opisthosoma, with a longitudinal light stripe with indented borders and arrow-shaped ( Fig. 3A ). Light brown venter of opisthosoma ( Fig. 3B ). Total length 7.45. Carapace 4.15 long and 3.08 wide. Eye diameters: AME 0.18, ALE 0.15, PME 0.22, PLE 0.19. Leg measurements: I: femur 4.45/ patella 1.75/ tibia 4.55/ metatarsus 4.18/ tarsus 1.71/ total 16.64; II: 3.77/ 1.65/ 3.51/ 3.52/ 1.37/ 13.82; III: 3.45/ 1.35/ 2.81/ 3.47/ 1.31/ 12.39; IV: 4.70/ 1.58/ 4.04/ 5.42/ 1.81/ 17.55. Leg formula 4123. Leg spination: tibia I and II v2-2-2-2-2, r1-1-0, p1- 1-0, III and IV v2-2-2, r1-1-0, p1,1,0; metatarsus I, II and III v2-2-2, r1-1-1, p-1-1-1, IV v1-1-1-1-2-2, r1-1-1, p1-1-1. Palp: short tibia, approximately two-thirds of cymbium length; dorsal branch of RTA elongated and with several internal folds and rounded tip; ventral branch of RTA short ( Fig. 4A–B ); ventral apophysis short and slightly curved retrolaterally ( Fig. 4A–B ). Cymbium with an elongated retrolateral dorsal projection and a short retrolateral ventral projection ( Fig. 4A–B ). Curved embolus, with a strong probasal projection ( Fig. 4A–B ). Cup-shaped median apophysis curved prolaterally and with a small distal projection and an elongated basal projection ( Fig. 4A–B ).

Female (paratype, IBSP 135435). Coloration as in male, but darker ( Fig. 3C–D ). Total length 9.18. Carapace 4.14 long and 3.00 wide. Eye diameters: AME 0.17, ALE 0.19, PME 0.21, PLE 0.18. Leg measurements: I: femur 3.27/ patella 1.79/ tibia 2.91/ metatarsus 2.44/ tarsus 1.05/ total 11.46; II: 2.98/ 1.59/ 2.45/ 2.13/ 0.97/ 10.12; III: 2.64/ 1.40/ 2.12/ 2.41/ 0.91/ 9.48; IV: 3.83/ 1.59/ 3.19/ 3.91/ 1.34/ 13.86. Leg formula 4123. Leg spination: tibia I and II v2- 2-2-2-2, r0-0-0, p0-0-0, III v2-2-2, r1-1-0, p1-1-0 and IV v2-2-2, r1-1-0, p1-1-0; metatarsus I and II v2-2- 2 r0-0-0 p0-0-0, and III v2-2-2, r1-1-1, p-1-1-1, IV v1-1-1-1-2- 2, r1-1-1, p1-1-1. Epigynum: median field cordiform with projected posterior margin ( Fig. 4C ); lateral spurs partially covered by the median field and with rounded tip ( Fig. 4C ). Internal genitalia: well-developed spermathecal base and slightly enlarged copulatory ducts ( Fig. 4D ).

Variation. Four males: total length 7.12–8.52 carapace length 4.01–4.51, femur I 4.06–5.00; 2 females: total 9.64–9.87, carapace length 4.54–5.07, femur I 3.58–3.71.

Distribution. Coastal Atlantic Rain Forest, near Todos os Santos Bay, northeastern Brazil, state of Bahia ( Fig. 7 ).

Figures

FIGURE 3. Isoctenus cabula new species, habitus. A–B, male; A, dorsal view; B, ventral view. C–D, female; C, dorsal view; D, ventral view.

FIGURE 4. Isoctenus cabula new species. A–B, male palp. A, ventral view; B, retrolateral view; C, female epigynum; D, vulva.

FIGURE 7. A–B, Geographic distribution records of Isoctenus jussara new species, I. cabula new species, and I. botocudos new species, and new records of Isoctenus areia. A, South America with demarcation of northeastern Brazil; B, Close up of the Brazilian northeastern regions where the species are distributed.