Eustiromastix guianae (Caporiacco, 1954)

Courtial, Cyril, Picard, Lionel, Ysnel, Frederic & Petillon, Julien, 2014, Validation of Eustiromastix guianae (Caporiacco, 1954) (Araneae, Salticidae) with a first description of the female, and additions to the salticid fauna of French Guiana, ZooKeys 420, pp. 11-18 : 13-16

Taxon classification Animalia Araneae Salticidae

Eustiromastix guianae (Caporiacco, 1954)

Eustiromastix guianae (Caporiacco, 1954): 176-177, figure 65, 65a; Galiano, 1979: 185.

Material.

Holotype: male (MNHN): French Guiana, Charvein. 7 females, 3 males and 1 subadult male Trinité NNR, 04°36'02"N, 53°24'43"W, 09.XII.2010, Julien Pétillon and Cyril Courtial. Specimens have been deposited in the Museum National d’Histoire Naturelle, Paris (male collection number: AR 15000; female collection number: AR 15001).

Diagnosis.

Among salticids, the differenciation between genera of the Plexippeae group is especially complex ( Galiano 1979) and only based on genitalia. Eustiromastix and Freya are close relatives. Freya is distinguished by its short thick pedipalp and tibial apophyses often rectangular and wide, and the solid and robust embolus, while Eustiromastix presents a longer pedipalp with a very long thin embolus ( Galiano 1979) and an apically curved cymbium. Females are characterised by the wide, flattened and folded copulatory ducts, which are as wide as the spermathecae ( Santos and Romero 2004). Eustiromastix guianae differs from all species of the genus by the shape of the embolus, the presence of a long median apophysis and the small pointed tibial apophysis. The female is distinguished by the strong vertical ducts and the large openings on the epigyne.

Redescription of the male

(holotype from Charvein).Figs 1A, B; 2 A–D; 5A. Total length 6.54. Prosoma: carapace 2.95 long, 2.35 wide and 1.83 high. Carapace: darkish brown. Cephalic region: black, and darker than thoracic region. Diameter of PME: 0.34; PLE: 0.14; AME: 0.58; ALE: 0.46. Distance PLE-PLE: 1.94; PME-PME: 2.01; PME-PLE: 0.27. Chelicerae: 1.10 long and 0.77 wide, dark brown. One promarginal and two retromarginal teeth. Legs: light brown, with dark annulations. Leg formula 3412. Length of femur: I 2.09, II 1.84, III 2.55, IV 2.27; patella: I 1.29, II 1.04, III 1.17, IV 0.87; tibia: I 1.80, II 1.32, III 1.42, IV 1.40; metatarsi: I 1.26, II 1.10, III 1.70, IV 1.83; tarse: I 0.66, II 0.62, III 0.61, IV 0.70.

Spination: femur I-III d1-1-1, r2-2 p2-2, IV d1-1-1, r1; patella I-II p1, III-IV p1, r1; tibia I-II v2-2-2, III-IV v1-2, p3, r3, d1; metatarsi I-II v2-2, III-IV v2-2, p1, r1, d2-2-2. Abdomen 3.71 long.

Dorsum: greyish with diffuse pale spots, and a median, longitudinal light brown stripe between a pair of longitudinal narrow stripes of white scales anteriorly and a white chevron posteriorly in fresh specimens (see Fig. 5A). Abdominal pattern with a median dark brown band.

Male palp as in Fig. 1A, B. Cymbium flattened apically (Fig. 2A), small retrolateral tibial apophysis, pointed internally in dorsal view (Fig. 2D). Long embolus with an elongated median apophysis at about one third of the total length of the embolus (Fig. 2B, C).

Locality: Charvein.

Female.

Figs 3A, B; 4 A–C; 5B. Total length: 7.51. Prosoma: carapace 2.75 long, 2.19 wide, and 1.59 high. Carapace: dark brown. Cephalic region: darker than the thoracic region. Diameter of PME: 0.29; PLE: 0.10; AME: 0.62; ALE: 0.32. Distance PLE-PLE: 1.75; PME-PME: 1.83; PME-PLE: 0.30. Chelicerae: 0.83 long 0.49 wide. Legs formula 4312. Length of femur: I 1.66, II 1.52, III 1.85, IV 1.89; patella: I 0.80, II 0.69, III 0.85, IV 0.71; Tibia: I 1.29, II 1.08, III 1.13, IV 1.30; metatarsi: I 0.74, II 0.64, III 1.16, IV 1.46; tarsi: I 0.62, II 0.58, III 0.67, IV 0.67. Spination: femur I-II d1-1-1, p2, III d1-1-1, p1, r1, IV d1-1-1, r1; patella: I-II p1, III-IV r1; tibia: I-II v2-2-2, p1, III-IV v1-2, r1-1-1, d1, p1-1-1; metatarsi: I-II v2-2, III d2-1-2, r1, v2-2, IV d2-2, v2-2, r1. Abdomen: 3.66 long. Dorsum: greyish to blackish (Fig. 5B) with a diffuse pale chevron in median part and a small white spot lateraly. Epigyne and spermathecae: as in Fig. 3A, B. Epigyne with two deep circular genital openings (Figs 3A, 4A). Insemination ducts: long and parallel (Figs 3B, 4B, C). Spermathecae: almost round and small at the base of the vulva (Fig. 4B, C).

Variation.

Male: Total length: 6.50-7.17, carapace length: 2.40-3.38, carapace width: 2.26-2.66 (n=4). Female: total length: 6.32-7.51, carapace length: 2.75-3.11, carapace width: 2.19-2.31 (n=7).

Habitat.

all specimens were collected together, including males in couple with females in tropical rain forest from beating and sweeping low vegetation.

Distribution.

known only from two localities in French Guiana (Charvein and Trinité NNR) Figure 1 of Suppl. material 1.