Onocolus ankeri, Teixeira & Machado, 2019

Teixeira, Renato Augusto & Machado, Miguel, 2019, On Neotropical crab spiders: description of a new species of Onocolus (Araneae: Thomisidae), Zootaxa 4657 (1), pp. 188-190 : 188

Onocolus ankeri sp. nov. ( Fig. 1 A–F)

[zoobank: urn:lsid:zoobank.org:act:126D850C-80CB-452A-A5A2-AA4D7304E657 ]

Type material: Holotype: BRAZIL: Pará: Melgaço, Castanhal do Jacaré , 1°44’13.5”S, 51°25’32.8”W, 1 female, 15 April 1997, J.A.P. Barreiros ( MPEG 35307 ).

Paratypes: BRAZIL: Roraima: Alto Alegre, Aldeia Budu , 3°12’09”N, 63°23’30”W, 1 female, 20 July to 05 August 2009, C. Kirsh ( IBSP 151198) . COLOMBIA: Caquetá: Solano (Parque Nacional Chiribiquete), 0°44’44,80”N, 72°44’17”W, 1 female, 25 June 2000, F. Quevedo ( ICN-AR 8979 ) .

Etymology. The epithet is an homage to Dr. Arthur Anker, who kindly provided us with photos of a live specimen. The name was chosen through a popular survey proposed by the Museu de Ciências e Tecnologia da Pontifícia Universidade Católica do Rio Grande do Sul (MCTP—PUCRS) to promote science popularization.

Diagnosis. Females of O. ankeri sp. nov. show the characteristic green body coloration as other females of the genus ( Figs 1A – B , live specimens) and resemble those of O. simoni Mello-Leitão in the shape and disposition of the copulatory ducts, with wide anterior curves forming a pair of primary spermathecae ( Fig. 1F ). However, the new species is distinct from all its congeners by presenting an accentuated curvature on its anterior tibiae (I and II) and three robust pairs of lateral projections on the opisthosoma ( Figs 1A, 1C ). Also, O. ankeri sp. nov. presents diagnostic setiferous tubercles on the median area of the prosoma, which are black pigmented and remarkably contrasting with the green background of the tegument ( Figs 1A, 1C, 1D ).

Description (Holotype). Anterior eye row recurved, posterior eye row slightly procurved; prosoma whitish-green with darker green spots radially disposed on the prosomal ridges ( Figs 1 A–D). Legs with same coloration as prosoma; anterior femora robust, with median black spot on the mesial surface (well developed on femora I and smaller on femora II); metatarsi and patellae II suffused with many dark spots ( Figs 1A, 1C ). Opisthosoma with three pairs of dorsal sigil- lae (the median pair largest and most noticeable); three pairs of opisthosomal projections disposed laterally, the anterior and median pairs of equivalent size and the posterior pair more robust and longer ( Figs 1A, 1C ). Epigynal plate wide and flattened, with copulatory openings oriented anteriorly; copulatory ducts long and hyaline on their first portion (before reaching the secondary spermathecae S2), getting gradually sclerotized along their trajectory towards the primary sper- mathecae S1 ( Figs 1E, 1F ). Measurements: eyes diameters and eyes interdistances: AME 0.12, ALE 0.16, PME 0.15, PLE 0.11, AME-AME 0.18, AME-ALE 0.08, PME-PME 0.34, PME-PLE 0.15, MOQ length 0.53, MOQ width 0.62; leg formula: 2-1-3-4: leg I—femur 5.74/ patella 2.66/ tibiae 3.56/ metatarsus 3.22/ tarsus 1.71/ total 16.89; II—5.44/ 2.61/ 4.02/ 3.21/ 1.73/ 17.01; III—2.34/ 1.33/ 1.88/ 1.36/ 0.57/ 7.48; IV—2.06/ 1.30/ 2.24/ 1.28/ 0.58/ 7.46. Total body length 8.85; prosoma 5.05 length, 5.32 wide; opisthosoma length 3.75 (including the projections); clypeus 0.25 height; sternum 2.16 length, 1.95 width; endites 1.20 length, 0.51 width; labium 0.79 length, 0.85 width.

Figures

FIGURE 1. Onocolus ankeri sp. nov. A–B Live specimens photographed by Arthur Anker at the surroundings of Mamori Lake, near Manaus, Brazil (A habitus dorsal, B prosoma frontal); C–D preserved specimens from MPEG 35307 (C habitus dorsal, D prosoma frontal); E–F epigynum from IBSP 151198 (E epigynum ventral, F vulva dorsal). Arrows indicate the course of the copulatory ducts system. Abbreviations: CO—copulatory openings; S1—primary spermathecae; S2—secondary spermathecae.