Isoctenus jussara, 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 : 178-181

Isoctenus jussara new species

Figures 1 , 2 , 7

Type material. Male holotype from Toca da Esperança, Jussara , 11º02’S, 41º58’W, Bahia, Brazil, 12–18.VII.2000, E.F. Ramos et al. coll., deposited in IBSP 130548. Female paratype from Toca do Índio , Central, 11º08’S, 42º06’W, Bahia, Brazil, 12–18.VII.2000, E.F. Ramos et al. coll., deposited in IBSP 130550 .

Additional material examined. BRAZIL. Bahia: Central, Toca do Índio, 11º08’S, 42º06’W, 1 male and 1 female, 12–18.VII.2000, E.F. Ramos et al. coll. (IBSP 130549); Toca do Índio , 5 males and 2 females, 12– 18.VII.2000, E.F. Ramos et al. coll., pitfall (IBSP 130533; 130534; 130543; 130544, 130545; 130546; 130547); Jussara, Toca da Esperança , 11º02’S, 41º58’W, 2 males, 12–18.VII.2000, E.F. Ramos et al. coll. (IBSP 130538); Toca da Esperança , 5 males and 1 female, 12–18.VII.200, E.F. Ramos et al. coll., pitfall (IBSP 130535; 130536; 130537; 130540; 130541; 130542) .

Etymology. The species name is a toponym in apposition referring to the type locality. The name Jussara comes from the Tupi word ii’sara or yu’sara, and it means itch or burning. The word was used to designate palm trees of the genus Euterpe Martius 1824 . Jussara is also a common female name in Brazil.

Diagnosis. Males of Isoctenus jussara new species resemble those of I. ordinario Polotow & Brescovit, 2009 by the elongated dorsal branch of RTA and truncated ventral branch of RTA, but can be distinguished by the shorter palpal tibia, the basal position of the RTA in the tibia, and the cymbium with larger retrolateral ventral projection ( Fig. 2A–B ) whereas the latter species can be distinguished by the longer palpal tibia, distal position of the RTA in the tibia, and cymbium with a shorter retrolateral ventral projection (see Polotow & Brescovit 2009: fig. 9A–B). Females of Isoctenus jussara new species resemble those of I. ordinario by the squared-shaped median field of the epigynum ( Fig. 2C ), but can be distinguished by the wider median field of the epigynum ( Fig. 2C ), while I. ordinario presents a narrower field ( Polotow & Brescovit 2009: fig. 9C).

Description. Male (holotype, IBSP 130548). 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. 1A ). Sternum, endites, labium, and legs light reddish brown ( Fig. 1B ). Brownish dorsum of opisthosoma, with a longitudinal light stripe with indented borders ( Fig. 1A ). Light brown venter of opisthosoma ( Fig. 1B ). Total length 7.25. Carapace 4.17 long and 3.31 wide. Eye diameters: AME 0.17, ALE 0.17, PME 0.24, PLE 0.19. Leg measurements: I: femur 3.80/ patella 1.53/ tibia 3.74/ metatarsus 3.33/ tarsus 1.70/ total 14.10; II: 3.41/ 1.56/ 3.02/ 3.20/ 1.20/ 12.39; III: 3.03/ 1.32/ 2.51/ 3.15/ 1.06/ 11.07; IV: 4.22/ 1.49/ 3.92/ 5.95/ 1.44/ 17.02. Leg formula 4123. Leg spination: tibia I and II v2-2-2-2-2, r1-0-0, p0-1-0, III v2- 2-2, r1-1-0, p1,1,0 and IV v2-2- 2, r1-0-1, p1-0-1; metatarsus I, II and III v2-2-2, r1-1-1, p-1-1-1, IV v1-1-1-1-1-1-2-2, r1-1-1, p1-1-0. Palp: short tibia, elongated retrolateral tibial apophysis, and depression in the dorsal branch; ventral apophysis slightly curved retrolaterally ( Fig. 2A–B ); RTA with ventral branch slightly elevated and truncated ( Fig. 2B ). Cymbium with a short retrolateral dorsal projection and a short, rounded, retrolateral ventral projection ( Fig. 2A–B ). Curved embolus, with a strong probasal projection ( Fig. 2A–B ). Cup-shaped median apophysis curved prolaterally and with a small distal projection and a large basal projection ( Fig. 2A–B ).

Female (paratype, IBSP 130550). Coloration as in male, but darker ( Fig. 1C–D ). Total length 8.65. Carapace 4.31 long and 3.48 wide. Eye diameters: AME 0.19, ALE 0.14, PME 0.25, PLE 0.21. Leg measurements: I: femur 3.35/ patella 1.85/ tibia 3.10/ metatarsus 2.47/ tarsus 1.05/ total 11.82; II: 3.16/ 1.70/ 2.51/ 2.46/ 1.03/ 10.86; III: 2.85/ 1.45/ 2.20/ 2.63/ 1.00/ 10.13; IV: 3.93/ 1.55/ 3.44/ 4.21/ 1.33/ 14.46. Leg formula 4123. Leg spination: tibia I v2-2-2- 2-2, r0-0-1, p0-0-1, II v2-2-2-2-2, r0-0-0, p0-0-0, III v2-2-2, r1-1-1, p1-1-1 and IV v2-2- 2, r1-1, p1-1; metatarsus I v2-2-2, r0-0-1, p0-0-1, II v2-2-2 r0-0-0 p0-0-0, and III v2-2-2, r1-0-1, p-1-1-1, IV v1-1-1-1-1-1-1-2- 2, r1-1-1, p1-1-1. Epigynum: median field cordiform ( Fig. 2C ); elongated lateral spurs, partially covered by the median field and with a truncated tip. Internal genitalia: well-developed spermathecal base and slightly enlarged copulatory ducts ( Fig. 2D ).

Variation. Six males: total length 6.15–7.76, carapace length 3.77–4.60, femur I 3.63–4.55; 3 females: total length 8.65–14.18, carapace 4.31–6.17, femur I 3.35–4.36.

Distribution. Collected outside caves in northern Chapada Diamantina mountains, state of Bahia, northeastern Brazil ( Fig. 7 ).

Figures

FIGURE 1. Isoctenus jussara new species, habitus. A–B, male; A, dorsal view; B, ventral view. C–D, female; C, dorsal view; D, ventral view.

FIGURE 2. Isoctenus jussara 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.