Trichothyse karoo Haddad & Sankaran 2025, sp. nov.
Creators: name: Sankaran, Pradeep M.
name: Haddad, Charles R.
name: Tripathi, Rishikesh
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Gnaphosidae
Trichothyse
Trichothyse karoo

description: Trichothyse karoo Haddad & Sankaran sp. nov.
Figs 3, 7, 11, 17, 42–57
Type material. Holotype ♂: SOUTH AFRICA: Western Cape: Matjiesfontein, Farm Jagerskraal, 33°13’19.6’’S, 20°24’35.8’’E, 975 m a.s.l., 18.X.2015, leg. Z. Mbo (hand collecting, karoo veld) (NCA 2016 /2262).
Paratypes: SOUTH AFRICA: Western Cape: Laingsburg, Anysberg Nature Reserve, 33°28.454’S, 20°40.696’E, 660 m a.s.l., 8.IX–8.X.2015, leg. Z. Mbo (pitfall traps, riparian woodland), 1♂ (NCA 2016 /2493); Matjiesfontein, Farm Jagerskraal, 33°13’28.6’’S, 20°24’29.8’’E, 995 m a.s.l., 16.X.2015, leg. Z. Mbo (hand collecting, karoo veld), 1♀ (NCA 2016 /2243); Same locality, 33°13’48.1’’S, 20°24’54.4’’E, 1045 m a.s.l., 10.IX– 15.X.2015, leg. Z. Mbo (pitfall traps, open ground), 1♂ (NCA 2016 /2224); Montagu, Les Hauts de Montagu, 33°48’54.9’’S, 20°09’04.5’’E, 360 m a.s.l., VII–XII.2016, leg. W. Jubber (hand collecting), 1♂ (NCA 2017 /521).
Etymology. The specific epithet is a noun in apposition referring to the habitat in which it was collected, the Nama Karoo Biome of South Africa.
Diagnosis. Males of T. karoo sp. nov. are similar to those of T. zuluensis comb. nov. in the general structure of the palp but can be distinguished by the different passage of the sperm duct, the more gradual curvature of the embolus (Figs 3–4, 54), and the shorter basal section and the longer/sharper dorsal branch of the RTA in retrolateral view (Figs 7–8, 55). Females of T. karoo sp. nov. share with T. fontensis and T. zuluensis comb. nov. the almost parallel mesal margins of the primary spermathecae but can be distinguished from all their congeners by the presence of a sclerotised posterior mesal ridge that terminates in a small teardrop-shaped atrium centrally in the epigyne (cf. Figs 9, 13, 15, 19 and Figs 56–57).
Description. Male (holotype, Matjiesfontein, NCA 2016/2262, Figs 42–47). Carapace, clypeus, chelicerae, labium, endites and sternum deep orange-brown (Figs 42–45); legs deep yellow-brown, with black mottling, femora slightly darker than other segments (Figs 46–47); eye field slightly darker than rest of carapace (Figs 43–44); abdomen dark grey dorsally, almost black laterally; spinnerets dark grey; venter creamy-grey. Carapace with faintly darker striae radiating from fovea, densely covered with white appressed hairs, cephalic part, and posterior slope with several stiff, erect black setae. Eye field as in genus description (Figs 43–44). Fovea narrow, longitudinal, straight, dark brown. Anterior surface of cheliceral paturon with numerous long black setae; promargin with low keel ending in small denticle, with additional distal tiny denticle (Fig. 45; arrow); keel continuing along entire length of promargin; retromargin without keel or denticle. Abdomen oval, hirsute; dorsum anteriorly with narrow, shiny brown scutum extending slightly less than ½ abdominal length, with three pairs of distinct oval sigilla, two pairs close together near posterior of scutum, at ⅓ abdomen length, third pair just behind midpoint (Fig. 42). Metatarsi I–II and all tarsi with well-developed complete scopulae (Figs 46–47), on metatarsi III and IV restricted distally. Spinnerets hirsute. Body length 5.40. Carapace 2.60 long, 1.76 wide. Abdomen 3.22 long, 1.80 wide. Eye sizes and interdistances: ALE 0.14, AME 0.17, PLE 0.14, PME 0.13; ALE–PLE 0.08, AME–AME 0.05, AME–PME 0.16, PME–PLE 0.09, PME–PME 0.10. AME and ALE nearly contiguous. Clypeus height at AMEs 0.12, at ALEs 0.10. Chelicerae 0.83 long. Length of palp and legs: palp 2.10 [0.73, 0.36, 0.23, 0.78], I 5.77 [1.70, 1.05, 1.23, 1.09, 0.70], II 5.53 [1.62, 0.98, 1.19, 1.08, 0.66], III 5.26 [1.56, 0.82, 1.12, 1.13, 0.63], IV 7.01 [1.90, 1.05, 1.43, 1.85, 0.78]. Leg formula: 4123. Spination of palp: femur pl 1 do 2, patella pl 1 do 1, tibia pl 1, tarsus plv 1 rlv 1; legs: femur I–II pl 1 do 3, III–IV pl 2 do 3 rl 2; patella I, II, IV spineless, III rl 1; tibia I–II vt 2, III pl 4 rl 2 plv 1 rlv 1 vt 3, IV pl 3 rl 2 plv 2 rlv 1 vt 2; metatarsus I–II plv 1 rlv 1, III pl 4 rl 2 plv 1 rlv 1 vt 3, IV pl 4 rl 4 plv 2 rlv 2 vt 3.
Palp (Figs 3, 7, 54–55): segments yellow-brown, cymbium darker (Figs 3, 7). RTA with stout base, with slender finger-like ventral branch and slightly shorter sharply pointed triangular dorsal branch (Figs 3, 7, 54–55). Cymbial flange indistinct, approximately half the length of cymbium, smooth along most of its length. Tegulum elongate-oval, sac-like (Figs 3, 54). Conductor membranous, passing behind embolus, with proximal part parallel to embolus and smoothly rounded apex directed retrolaterally (Figs 3, 7, 54–55). Embolus arising prolaterally, then curving retrolaterally at distal part to form a claw-shaped tip, directed at 3-o’clock (Figs 3, 7, 54–55).
Female (paratype, Matjiesfontein, NCA 2016/2243, Figs 48–53). General aspects essentially as in male except the following: habitus colour lighter than male, legs yellow-brown, with metatarsi and tarsi slightly darker (Figs 48, 52–53). Abdomen without dorsal scutum, with three pairs of distinct oval sigilla, first two pairs at ¼ abdomen length and third pair at ½ abdomen length (Fig. 48). Body length 7.12. Carapace 2.86 long, 1.80 wide. Abdomen 3.91 long, 2.16 wide. Eye sizes and interdistances: ALE 0.16, AME 0.17, PLE 0.15, PME 0.14; ALE–PLE 0.13, AME–AME 0.09, AME–PME 0.15, PME–PLE 0.10, PME–PME 0.11. Clypeus height at AMEs 0.11, at ALEs 0.10. Chelicerae 0.95 long. Length of palp and legs: palp 2.24 [0.81, 0.35, 0.36, 0.72], I 6.08 [1.80, 1.10, 1.28, 1.12, 0.78], II 6.03 [1.79, 1.11, 1.28, 1.17, 0.68], III 5.72 [1.65, 0.92, 1.12, 1.23, 0.80], IV 7.41 [2.04, 1.10, 1.57, 1.88, 0.82]. Leg formula: 4123. Spination of palp: femur pl 1 do 2, patella pl 1, tibia pl 2 do 1 rl 1 plv 2, tarsus pl 1 rl 1 plv 2 rlv 2 vt 2; legs: femur I pl 1 do 3, II pl 2 do 3, III pl 2 do 3 rl 2, IV pl 1 do 2 rl 1; patella I, II and IV spineless, III pl 1 rl 1; tibia I–II vt 1, III pl 4 rl 2 plv 2 rlv 1 vt 2, IV pl 3 rl 2 plv 2 rlv 1 vt 2; metatarsus I plv 1, II plv 1 rlv 1, III pl 4 rl 3 plv 1 rlv 1 vt 3, IV pl 4 rl 4 plv 2 rlv 2 vt 4.
Genitalia (Figs 11, 17, 56–57): epigyne originally hirsute, hairs lost during cleaning, with narrow median hourglass-shaped ridge in posterior half formed by posterior lobes, terminating anteriorly in small teardrop-shaped atrium in centre of epigyne (Figs 11, 56; arrow). Copulatory openings indistinct, at posterior edge of posterior lobes. Copulatory ducts very short, partly obscured by primary spermathecae (Figs 17, 57). Primary spermathecae parallel-sided, separated by slightly less than half their width (Figs 17, 57). Paired secondary spermathecae short, globular, partly obscured by primary spermathecae (Figs 17, 57). Fertilization ducts broad, undulating, diverging (Figs 17, 57).
Variation. Male (n = 4): body length 4.60–6.05, mean 5.28.
Distribution. Known only from the semi-arid south-western parts of South Africa (Fig. 120).
description: Published as part of Sankaran, Pradeep M., Haddad, Charles R. & Tripathi, Rishikesh, 2025, A review of the ground spider genus Trichothyse Tucker, 1923 (Araneae, Gnaphosidae), pp. 39-70 in Zootaxa 5583 (1) on pages 48-50, DOI: 10.11646/zootaxa.5583.1.2, http://zenodo.org/record/14798099