Afrotrichona, Tanasevitch, 2020

Tanasevitch, Andrei V., 2020, Linyphiid spiders collected by V. Mahnert in Kenya, with the description of a new genus and two new species (Arachnida: Araneae), Revue suisse de Zoologie 127 (2), pp. 349-360 : 350

Genus Afrotrichona gen. nov.

Type species: Afrotrichona mahnerti sp. nov.

Etymology: The generic name is a combination of two words: “Afro”, referring to the “ terra typica ”, and a part of the generic name Trichoncoides (see taxonomic remarks below). The gender is feminine.

Diagnosis: The genus contains medium-sized erigonines (total length 1.90-2.25) characterized by the following combination of somatic and genitalic characters:

1) Carapace unmodified in both sexes ( Figs 1-3 ), eyes normal, not enlarged, cephalic pits (= sulci) absent.

2) Chaetotaxy formula 1.1.1.1. Metatarsus IV without trichobothrium. TmI 0.29-0.32.

3) Palpal tibia modified ( Figs 8, 10 ).

4) Paracymbium small, narrow, strongly curved and almost forming a loop ( Fig. 8 ).

5) Distal suprategular apophysis moderately developed ( Figs 8, 12 ).

6) Embolus twisted. Radix with an anterior process guiding and protecting embolus ( Figs 8-9, 11 ).

7) Epigyne with a visor-shaped structure overhanging its cavity, lateral walls forming an arch ( Figs 4-7 , 13- 15 ).

Taxonomic remarks: The new Afrotropical erigonine genus bears some resemblance to the Ancient Mediterranean Trichoncoides Denis, 1950b . Namely, the embolic division in Afrotrichona mahnerti sp. nov. is similar to that in T. piscator ( Simon, 1884) and T. striganovae Tanasevitch & Piterkina, 2012 by the presence of an anterior radical process guiding and protecting the embolus ( Figs 9, 11 cf. Tanasevitch & Piterkina, 2012: fig. 7). The presence of a “visor” in the epigyne of A. mahnerti sp. nov. makes it resemble the epigyne of Trichoncoides members ( Figs 13-14 cf. Tanasevitch & Piterkina, 2012: figs 40-45). The new genus is clearly distinguished from Trichoncoides by the chaetotaxy formula (1.1.1.1 in Afrotrichona gen. nov. versus 2.2. 1.1 in Trichoncoides ), by the unmodified male carapace, i.e. absence of a special group of spines on its cephalic part, as well as by the absence of a median septum in the epigyne of females.

Species included: Only the type species.

Distribution: Kenya.

Figures

Figs 1-7. Photographs of Afrotrichona mahnerti sp. nov., male paratype (1-2) and female paratype (3-7). (1, 3) Habitus, dorsal view. (2) Prosoma, dorso-frontal view. (4-5) Abdomen, ventral and postero-ventral view, respectively. (6-7) Epigyne, ventral and postero-ventral view, respectively.

Figs 8-15. Details of male palp and epigyne structure of Afrotrichona mahnerti sp. nov., male paratype (8-12) and female paratype (13-15). (8-9) Right palp, retrolateral and ventro-prolateral view, respectively. (10) Palpal tibia, dorsal view. (11) Embolic division, ventro-prolateral view. (12) Distal suprategular apophysis, lateral view. (13-15) Epigyne, ventral, postero-ventral and lateral view, respectively.