Research Article |
Corresponding author: Duniesky Ríos-Tamayo ( riostamayo.dnk@gmail.com ) Academic editor: Bernhard A. Huber
© 2023 Duniesky Ríos-Tamayo, Robin Lyle, Catherine L. Sole.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Ríos-Tamayo D, Lyle R, Sole CL (2023) Ekapa, a new genus of mygalomorph spiders (Araneae, Entypesidae) from South Africa. African Invertebrates 64(1): 1-12. https://doi.org/10.3897/afrinvertebr.64.97018
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A new genus of mygalomorph spider Ekapa gen. nov., is described from South Africa. The new genus was formed to include the species Hermacha curvipes Purcell, 1902 and Hermacha nigra Tucker, 1917. These species are synonymized based on their somatic similarities, such as fovea shape, cheliceral teeth distribution, ocular pattern, presence of preening combs, and their close geographic distribution. The new genus proposed is distinguished by the presence of a projection in the retroventral side of the palpal tibia in males, together with a distinctive copulatory bulb shape; and in females by the shape of their spermathecae, with a high base and apical stalks that open into oval apical receptacles.
new genus, new species, new synonymy, systematics, taxonomy
The fauna of mygalomorph spiders from South Africa is poorly known and many of the current genera require revision (
In the present paper, we propose to synonymize the species H. curvipes and H. nigra, based on their morphological similarities observed through the examination of the type specimens and additional related material. Besides the similarities of the two species, the somatic characters and the morphology of the copulatory organs do not match the features of the genus Hermacha, and have not been observed in any other related genus. Thus, we propose the creation of a new genus, described here to accommodate these species.
The material studied here is deposited in the following institutions (curators are noted in brackets):
All measurements are given in millimeters and were taken from the left side of the specimen. Total length was measured without spinnerets. The photographs were taken using a high-resolution microscopy camera AxioCam MRc5 mounted on a Zeiss Axio Zoom V16 microscope. Extended focal range images were stacked using the ZEN module Z-stack software. Lengths of leg segments are always given in the same order: femur, patella, tibia, metatarsus, tarsus, and total. The male copulatory bulb and female genitalia were dissected using a microscalpel. The copulatory bulbs were photographed following the approaches of
Abbreviation and notation for leg spines follow
Abbreviations used in species descriptions are as follows: ALE, anterior lateral eyes; AME, anterior median eyes; D, dorsal; DB, dorsal basal; P, prolateral; PA, prolateral apical; PLE, posterior lateral eyes; PLS, posterior lateral spinnerets; PME, posterior median eyes; PMS, posterior median spinnerets; OQ, ocular quadrangle; R, retrolateral; RM retrolateral medial; RA, retrolateral apical; V, ventral; VB, ventral basal; VPOST, ventral posterior. In the notation of leg spines, an expression such as D–R, D–P indicates that the spines occupy the dorsal–posterior superior surfaces, or the dorsal–prolateral superior surfaces; 1:2 A, 3:4 B indicates that the spines or scopula referred to are on the apical half or basal three-fourths. In the description of the preening combs, II 2 or 3 PV indicates that the combs are on the second leg, composed by two or three setae and in prolateral-ventral position.
Hermacha curvipes Purcell, 1902, by present designation.
The new name “Ekapa” is taken from the type locality and means “Cape Town” in the Xhosa language. The gender is neutral.
The new genus can be distinguished from all other related genera in the family Entypesidae by the presence of a retroventral projection in the male palpal tibia (absent in all other entypesid genera; Figs
Given the morphological characters presented here, this new genus shows affinities with Afropesa, Hermacha and the Australian genus Stanwellia Rainbow & Pulleine, 1918 (currently belonging to the family Pycnothelidae), since they all present a retrolateral apical megaspine on tibia I. Nevertheless, Ekapa gen. nov. differs from them due to its characteristic retroventral projection on the male palpal tibia. Stanwellia spp, demonstrate a similar shape of the spermathecae (with a high base), but differ from Ekapa gen. nov. since they possess flexuous leg tarsi, and a straight thoracic fovea (
Cephalothorax and legs covered with short bristles; cephalothorax with dark setae on the margin, more abundant towards the posterior part. Thoracic fovea short, straight or slightly recurved. Eyes group broader than long, anterior row slightly procurved and posterior row recurved (Figs
Ekapa curvipes (Purcell, 1902), comb. nov.
Hermacha curvipes
Purcell, 1902: 377;
Hermacha nigra
Tucker, 1917: 110;
Syntypes
, 2 ♂♂: Hermacha curvipes (
Western Cape, Cape Town, Aug 1965, collector not indicated, 1 ♂ (
The holotype specimen (male,
As for the genus.
Male (NCA 2008/770, Figs
Ekapa curvipes, male (NCA 2008/770) A–D copulatory bulb A retrolateral view B ventral view C prolateral view D closeup of the tip, arrows indicate the two keels E, F distal segments of right pedipalp E retrolateral view, arrow indicates the projection in the retroventral side F prolateral view G–I tibia I G prolateral view H ventral view I retrolateral view.
Chaetotaxy
: Leg I: femur, 1-1-1 P, 1-1-1-1 D, 1-1 R; patella, 1-1 P; tibia, 1-1 P, 1 R (1/2 B), 2-1-2 V, and a strong apical spine (ventral posterior); metatarsus, 1-1 P, 1-2 V (1/2 A), strongly curved with a well-marked retrolateral elbow. Leg II: femur, 1-1-1 P, 1-1-1-1 D, 1-1-1-1 R; patella, 0; tibia, 1-1 P, 2-1-3 V; metatarsus, 1 P, 1-1 D, 1 RM, 2-2-2 V. Leg III: femur, 1-1-1 P, 1-1-1-1 D, 1-1-1 R; patella, 1-1 P, 1 R; tibia, 1-1-1 P, 1-1 D, 1-1 R, 2-2-3 V; metatarsus, 1-1-1 P, 1-1-1 D-P, 1-1-1 D-R, 2-2-3 V. Leg IV: femur, 1-1-1-1 P, 1-1-1-1 D, 1-1-1-1 R; patella, 1 R; tibia, 1-1 P, 1 DB, 1-1 R, 2-2-3 V; metatarsus, 1-1-1 P, 1-1-1 D-P, 1-0-1 D-R, 1-1-9-1 R, 2-1-1-3 V. Pedipalp: femur, 1 PA, 1-1-1 d; patella, 1 PA; tibia, 1-2-2 P, 1 D, 1 RA, developed retroventral projection (Fig.
Female (
Chaetotaxy
: Leg I: femur, 1 PA; patella, 1 PA; tibia, 1-1 P, 1-1-3 V; metatarsus, 2-1-1 V. Leg II: femur, 1-1-1-1 d, 1 PA; patella, 1-1 P; tibia, 1-1 P, 1-1-2 V; metatarsus, 1-1 P (1/2 B), 2-2-2 V. Leg III: femur, 1 db, 1-1 P, 1 RA; patella, 1-1-1 P, 1 R; tibia, 1-1 P, 1-1 D, 1-1 R, 2-2-3 V; metatarsus, 1-1-1 P, 1-1-1 D-P, 1-1-1 D-R, 2-2-3 V. Leg IV: femur, 1-1-1-1 d, 1 PA; patella, 1 R; tibia, 1-1 R, 2-2-2 V; metatarsus, 1-1-1 P, 1-1 D-P (1/2 ANT), 1-1-1-1 D-R, 2-1-1-1-3 V. Pedipalp: femur, 1 PA; patella, 1-1 p; tibia, 2-1-1-3 P, 1-2-3 V; tarsus, 2 P, 1 VB. Spermathecae: complete, a high base with two lateral stalks, with an elongated receptacle (Fig.
Known from the Western Cape Province.
This research was made possible through scholarships awarded to the senior author: CONICET, Partial financial support for short stays of research; Res D N° 4367, 28 dec. 2017. It is part of the NRF (National Research Foundation, South Africa) grant No: 141937/Reference No: SRUG200417514326 to Catherine Sole and the authors. Special thanks are due to Petro Marais for providing access to the National Collection of Arachnida, ARC, Pretoria, where the senior author was hosted during his visit. Thanks to Ian Engelbrecht (SANBI, South African National Biodiversity Institute) for assistance provided during the earlier stages of the draft. To Sergei Zonstein (The Steinhardt Museum of Natural History Tel Aviv University, Israel) for useful comments. We are thankful to the second reviewer for their valuable comments and recommendations which helped to improve the original manuscript. Thanks to Ian Millar and Shannon Mitchel for the language review. We also thank all the curators who provided specimens of Entypesidae from South Africa on loan.