Idiops petiti
Creators: name: Fonseca-Ferreira, Rafael
name: Guadanucci, José Paulo Leite
name: Yamamoto, Flávio Uemori
name: Brescovit, Antonio Domingos
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Idiopidae
Idiops
Idiops petiti

description: Idiops petiti (Guérin, 1838)
Figs 3B, 26
Acanthodon petitii Guérin, 1838: 163, pl. 47 figs 1–8.
Acanthodon santaremia O. Pickard-Cambridge, 1896: 733, pl. 34 fig. 13. Syn. Nov.
Idiops crulsi Mello-Leitão, 1930: 55, fig. 2. Synonymized by Bücherl et al. 1971: 128.
Idiops petiti – O. Pickard-Cambridge 1870: 107; 1896: 732, pl. 34 figs 9–12. — Mello-Leitão 1923: 48. — Bücherl et al. 1971: 121, fig. 5.
Idiops santaremius – Petrunkevitch 1911: 73.
Diagnosis
The male of Idiops petiti differs from that of other Neotropical species, except I. carajas, by having the palpal tibia with spines concentrated in the basal half of the retrolateral depression (Fig. 26C), the tibial apophysis with a narrow apical branch and rectangular in shape (Fig. 26G–H) and by the presence of a lateral lamella that extends along the median portion of the embolus (Fig. 26E–F). Differs from I. carajas by having the subapical portion of the embolus thin and straight (Fig. 26E–F) and the metatarsus of the leg I slightly curved and with a small prolateral projection on the apical half (Figs 26I). Females are distinguished from congeners, except I. carajas, by having the spermathecae with a large sclerotized trapezoidal base and V-shaped ducts (Fig. 26L). Differs from I. carajas by its large oval-shaped receptacula (Fig. 26L).
Type material
Holotype of Acanthodon petitii Guérin, 1838 BRAZIL – Pará • ♀; Santarém; BMNH 1890.7.1.320.
Holotype of Acanthodon santaremia O. Pickard-Cambridge, 1896
BRAZIL – Pará • juv.; Santarém; Mar. 1896; O. P.-Cambridge leg.; BMNH 1896.12.13.66.
Holotype of Idiops crulsi Mello-Leitão, 1930
BRAZIL – Pará • ♀; Oriximná, Rio Cuminá; G. Cruls leg.; MNRJ 0007. Lost in the fire of 2018.
The type specimen of Idiops petiti was originally deposited in a dry collection and subsequently rehydrated and stored in alcohol. Although clearly an adult female, the specimen has lost many legs and the spermathecae, because the abdomen was stuffed with cotton. This prevented a more detailed description. The type specimen of I. santaremius was examined and recognized as a juvenile of I. petiti.
Other material examined
BRAZIL – Amazonas • 2 ♂♂; Manaus, Fazenda Esteio; 2°23′3.00″ S, 59°51′15.00″ W; 6 Nov. 1985; B.C. Klein leg.; INPA 4590 to 4591 • 1 ♂; Benjamin Constant; 4°22′58″ S, 70°1′51″ W; 2014; P.S. Pompeu leg.; IBSP 243961 • 1 ♂; Jutaí, near the Rio Jutaí; 5º38′21.7″ S, 69º10′58.8″ W; 14–19 Mar. 2006; M.S. Hoogmoed leg.; MPEG 2579. – Pará • 2 ♂♂; Belterra, Flona Tapajós, Km 83; 3°31′1″ S, 55°4′23″ W; 2010; J.L. Freitas leg.; IBSP 218829, IBSP 218868 • 1 ♂; Almeirim, Jari; 1°1′33.122″ S, 52°34′2.785″ W; MPEG 7588 • 1 ♂; Senador José Porfirio; Trilha do Censo, Margem Direita, Rio Xingu; 2°35′27″ S, 51°57′14″ W; 25 Feb. 2001; MPEG 0113 • 1 ♂; Senador José Porfirio; Trilha do Acampamento, Margem Direita, Rio Xingu; 25 Feb. 2001; MPEG 0116 • 1 ♂; Jacareacanga, UHN de São Manoel; 9°13′32″ S, 56°59′56″ W; 16 Feb. 2009; W.U. Prado leg.; UFMG 3205 • 1 ♂; Jacareacanga; 21 Feb. 2009; W.U. Prado leg.; UFMG 3206. – Rondônia • 1 ♀; Monte Negro, LC25, Km 10; 10°14′49″ S, 63°24′16.8″ W; 19 Dec. 2013; P.H. Martins leg.; UFMG 24031.
Description
Male (MPEG 0116)
HABITUS. See Fig. 26A.
MEASUREMENTS. TBL 17.2, CL 7.4, CW 6.7, LL 0.9, LW 1.4, SL 4, SW 3.6.
COLOR. Carapace and legs reddish brown, with yellowish coxae, brownish sternum; abdomen grey (Fig. 26A–B)
PROSOMA. Carapace and ocular arrangement as shown in Fig. 26A. Eye tubercle: 0.7 long; 1.3 wide. AME-ALE distance 0.9. Eye diameters: AME 0.4, ALE 0.4, PME 0.2, PLE 0.4. Thoracic fovea procurved (Fig. 26A). Labium and sternum without cuspules (Fig. 26B). Basal segment of chelicerae with a prolateral row of 8 large teeth and 4 small retrolateral teeth, grouped in basal half, rastellum presenting 12–13 spines of same size.
LEGS. Tibia, metatarsus and tarsus I as shown in Fig. 26G. Leg I with double tibial apophysis. Apical branch twice the size of basal branch and with a conspicuous spine (Fig. 26H–I). Pseudoscopula: tarsus I–IV totally covered.
PALP. Elongated palpal bulb with slightly curved embolus and without torsion of subapical portion (Fig. 26D–F).
PALP AND LEG MEASUREMENTS. Palp = 12 (3.8, 3.3, 3.21, 1.7), I = 22 (6.8, 3.5, 5.1, 4.8, 1.8), II = 18.9 (6, 3, 4.4, 3.8, 1.7), III = 17 (4.7, 2.9, 3, 4.3, 2.1), IV = 24.2 (6.9, 3.6, 5.9, 5.1, 2.7).
SPINATION. Palp: Ti r19, Ta d0-0-4. Leg I: Fe d1-2-1, Pa v0-1-5, Ti v10-15-16, p0-1-0, Mt v6-8-14, p0-0-5, r0-0-4, Ta p3-4-4, r5-6-6. Leg II: Fe d1-2-1, Pa p0-0-2, Ti v5-7-12, p2-2-9, r1-2-4, Mt v6-6-7, p3-5-10, r3-3-4, Ta p4-4-4, r6-6-7. Leg III: Fe d1-2-1, Ti p2-3-6, Mt r6-3-8, Ta p5-8-8, r2-4-7. Leg IV: Fe d1-2-1, Ti v1-2-3, r0-1-2, Mt v1-3-3, p1-2-5, r0-3-5, Ta p5-5-8, r5-5-8.
Female (UFMG 24031)
HABITUS. See Fig. 26J.
MEASUREMENTS. TBL 13, CL 5.8, CW 4.9, LL 0.8, LW 2, SL 3.5, SW 3.5.
COLOR. Carapace and legs brown, light brown sternum (Fig. 22J–K). Abdomen grey.
PROSOMA. Carapace and ocular arrangement as shown in Fig. 26J. Eye tubercle: 0.6 long; 1 wide. AME-ALE distance 0.8. Eye diameters: AME 0.2, ALE 0.3, PME 0.2, PLE 0.4. Thoracic fovea procurved (Fig. J). Labium with 3 cuspules (Fig. 26K). Maxilla with 30 cuspules, distributed throughout anterior ventral half (Fig. 26K). Basal segment of chelicerae with a prolateral row of 7 large teeth and 4 small retrolateral teeth, grouped in basal half. Rastellum well developed, presenting 14–16 robust spines (Fig. 26K).
PALP AND LEG MEASUREMENTS. Palp = 9.6 (3, 2, 2.2, 2.4), I = 10.2 (2.8, 2.2, 2.3, 1.7, 1.2), II = 10.2 (3.3, 2.2, 2, 1.3, 1.4), III = 11.3 (3, 2.3, 2, 2.3, 1.7), IV = 15.2 (4, 3, 3.2, 2.9, 2.1).
SPINATION. Palp: Ti p5-6-9, r6-8-12, Ta p6-7-8, r8-8-9. Leg I: Pa v0-0-2, Ti v1-2-1, p4-6-9, r4-6-11, Mt v2-1-1, p8-6-8, r10-3-4, Ta v0-0-1, p3-4-4, r4-3-2. Leg II: Ti v1-1-1, p3-7-7, r0-1-2, Mt v1-1-1, p7-5-4, r1-2-2, Ta v0-1-1, p4-4-3, r2-2-1. Leg III: Fe d0-0-1, Pa d0-0-1, p4-5-8, r0-0-1, Ti v0-1-2, p3-4-5, r0-1- 4, Mt v2-1-2, p2-3-2, r2-2-1, Ta v1-2-3, p0-0-3. Leg IV: Fe d0-0-1, Pa p12-4-2, Ti v1-1-2, Mt v2-3-5, p0-1-2, Ta v1-2-3, p0-3-6.
SPERMATHECAE. Ducts with weakly sclerotized basal half and thickened and sclerotized apical half; asymmetric receptacula, with expansion of medial half (Fig. 26L).
Distribution
Brazil. Widely distributed in the Amazon region, with records for the North region (Amazonas, Pará and Rondônia) (Fig. 3B).
description: Published as part of Fonseca-Ferreira, Rafael, Guadanucci, José Paulo Leite, Yamamoto, Flávio Uemori & Brescovit, Antonio Domingos, 2021, Taxonomic revision of the Neotropical spiders of the genus Idiops Perty, 1833 (Araneae, Idiopidae), with description of four new species, pp. 1-71 in European Journal of Taxonomy 780 (1) on pages 47-50, DOI: 10.5852/ejt.2021.780.1581, http://zenodo.org/record/5761280