Mushimane gen. nov.

Type species.

Mushimane tswibilinki sp. nov.

Diagnosis.

This genus includes possibly the smallest known trachelids, with adults only ~ 1.8 mm in total length. Both sexes superficially resemble Falcaranea Haddad & Lyle, 2024 but are smaller, lighter in colour and have very different genitalic morphology. Males can be distinguished by from all other trachelids by the distinctive spiralling loop in the distal section of the sperm duct of the palp, close to the base of the embolus, which is short and spike-like (Fig. 15 A), whereas long, curved and sword-like in Falcaranea (Haddad and Lyle 2024: figs 143, 147). Females can be easily recognized by the broad diamond-shaped epigynal atrium, flanked by sclerotized ridges along its posterior margin (Fig. 15 C).

Description.

Small spiders, 1.79–1.84 mm in length; carapace creamy-yellow, yellow-brown in eye region (Fig. 13 A, B, F, G); carapace oval, broadest near middle of coxae II, gradually narrowed towards eye region, posterior margin straight (Fig. 13 A, F); fovea absent, reduced to broad shallow depression at ¾ carapace length (Fig. 14 A); carapace convex in lateral profile, slightly elevated from clypeus, highest just anterior to midpoint, with steeper slope in posterior quarter (Fig. 13 B, G); carapace surface smooth, with sparse short fine curved setae with small tuberculate bases (Fig. 14 A, B). All eyes surrounded by black rings (Fig. 13 A, F); AER slightly procurved in males, strongly procurved in females; clypeus height slightly larger than ½ AME diameter at AME, slightly less than ½ ALE diameter at ALE in males and slightly less than ⅓ ALE diameter in females; ALE slightly larger than AME in males, clearly larger in females; AME separated by distance equal to slightly less than ½ their diameter in males, equal to ⅓ their diameter in females; AME separated from ALE by narrow sliver, almost touching; PER slightly recurved, PLE slightly larger than PME in males, 1 ⅓ PME diameter in females; PME separated by distance equal to slightly less than their diameter; PME separated from PLE by distance equal to ⅔ PLE diameter. Chilum and cheliceral dentition not observed; endites with parallel lateral margins, mesal margins with yellow-brown longitudinal groove, distal margins with distinct serrula and dense maxillar hair tuft on mesal margins; labium hexagonal, slightly longer than wide, with broad base and rounded distal margin. Pleural bars sclerotised, isolated; sternum elongate shield-shaped, longer than broad, broadest between coxae II and III (Fig. 13 C, H), surface smooth centrally, sparsely covered in short straight setae; precoxal triangles present, intercoxal sclerites only observed between coxae I and II. Leg formula 1423 in both sexes, sparsely covered in long fine setae; leg I clearly longer and more robust in males (Fig. 13 A), only slightly more so in females (Fig. 13 F); ventral cusps absent on anterior legs and scopulate setae and spines absent on all legs in both sexes; femora I very slightly swollen in both sexes, with slightly convex dorsal surface, ventral surface straight (Fig. 13 D, I); patellar indentation on retrolateral side narrow; metatarsi III and IV with ventral preening comb at distal end (Fig. 13 E, J); tarsi with sparse tactile hairs, one basal and two medial pairs of trichobothria and numerous chemosensory setae (Fig. 14 C); trichobothria with slightly lowered distal plate, distal margin of hood overlapping plate, hood with four curved ridges, roughly concentric (Fig. 14 E); tarsal organ distal, at approximately ⅞ tarsus length (Fig. 14 C, D), only very slightly elevated from integument, surface finely wrinkled, opening oval and distally placed (Fig. 14 F); paired tarsal claws long, stout, with at least eight long, broad teeth and numerous tenant setae forming claw tufts in between (Fig. 14 D). Abdomen oval, cream, with two pairs of indistinct sigilla, with dorsal scutum in neither sex (Fig. 13 A, F); dorsum with very sparse fine setae; venter without sclerites or markings, sparsely covered in fine setae (Fig. 13 C, H); abdomen of both sexes with tip directed ventrally (Fig. 13 B, G), which is especially accentuated in the female studied by S. E. M .. Spinnerets short, conical, in compact group (Fig. 13 C, H), spigot detail only studied in female M. tswibilinki sp. nov.: ALS with one MAmp, one Nu and six Pi (Fig. 14 G); PMS with single mAmp, two Cy and six Ac (Fig. 14 H); PLS with two Cy and eight Ac (Fig. 14 I). Male palpal femur and patella without apophyses; palpal tibia with simple distal retrolateral apophysis (Fig. 15 A); tegulum oval in ventral view, with basal section of cymbium covering tegulum retrolaterally (Fig. 15 A, B), with short spike-like embolus originating prolaterally at distal end of tegulum (Fig. 15 A); sperm duct unique among Trachelidae, forming distinct spiralling loop internally in distal half of tegulum near base of embolus (Fig. 15 A). Female epigyne weakly sclerotised, occupying half of epigastric plate length (Fig. 13 H), with broad diamond-shaped atrium (Fig. 15 C); copulatory openings in lateral corners of atrium, with short copulatory ducts leading to anterolateral ST II; connecting ducts initially directed laterally, converging to globose posterolateral ST I, with fertilization ducts on their mesal margin (Fig. 15 D).

Etymology.

The name is a noun in the indigenous African Sesotho language for “ boy ” or “ little man ”, referring to the diminutive size of the type species. Gender masculine.

Composition.

Monotypic.