Trachecymbius tyume, Haddad & Lyle, 2024

Haddad, Charles R. & Lyle, Robin, 2024, Three new genera of arboreal dark sac spiders from southern Africa (Araneae: Trachelidae), Zootaxa 5399 (5), pp. 451-504 : 496-498

Trachecymbius tyume sp. nov.

Figs 170–188 , 198–214 , 219, 220 , 230–233

Etymology. The species name is a noun in apposition of Tyume Forest, the indigenous forest where the species was first discovered and where many of the known specimens were collected.

Diagnosis. The male of this species can be recognised by the short, strongly bent embolus with a rounded tip, and the presence of a pointed RTA and several small denticles on the dorsal surface of the palpal tibia ( Figs 230, 231 ). As in T. felis sp. nov., the cymbium contains two basal apophyses, but it can be distinguished by the dorsal apophysis being subdivided into two lobes and the ventral lobe being broad ( Fig. 214 ), while in T. felis sp. nov. the dorsal lobe is not divided and is finger-like, as is its ventral lobe ( Fig. 195 ). The female is easily recognised by the relatively narrow epigynal field compared to congeners (clearly longer than wide, as opposed to almost as long as wide) and the almost parallel connecting ducts of the spermathecae ( Figs 232, 233 ).

Male (holotype, Hogsback, NCA 2014/378). Measurements: CL 1.14, CW 0.93, AL 1.30, AW 0.95, TL 2.44, FL 0.17, SL 0.70, SW 0.55, AME-AME 0.03, AME-ALE 0.015, ALE-ALE 0.19, PME-PME 0.08, PME-PLE 0.10, PLE-PLE 0.37. Length of leg segments (sequence from femur to tarsus, and total): I 0.73 + 0.44 + 0.56 + 0.52 + 0.29 = 2.54; II 0.62 + 0.32 + 0.44 + 0.40 + 0.28 = 2.06; III 0.52 + 0.25 + 0.29 + 0.40 + 0.21 = 1.67; IV 0.70 + 0.29 + 0.51 + 0.52 + 0.23 = 2.25.

Carapace deep orange-brown, with faint black mottling ( Fig. 219 ); carapace finely granulate throughout, more pronounced on lateral slopes, absent on posterior slope behind fovea; fovea short, narrow, at ¾ CL. AER slightly procurved; clypeus height approximately ¾ AME diameter; ALE larger than AME; AME separated by distance equal to ½ their diameter; AME separated from ALE by distance equal to ¼ AME diameter; PER strongly recurved; PLE slightly larger than PME; PME separated by distance equal to their diameter; PME separated from PLE by distance equal to 1½ times PME diameter. Chelicerae and labium deep orange-brown, endites yellow; sternum bright yellow-orange, brown around borders. Abdomen oval, dorsum mottled grey, with indistinct pale yellowish scutum covering dorsum ( Fig. 219 ); two pairs of orange-brown sigilla, first pair oval, at ¼ AL, second a series of 4–5 oval sclerites at midpoint of abdomen; venter creamy-grey.Legs uniform yellow-brown, leg I slightly darker; all femora slightly darker and patellae slightly paler than tibiae, metatarsi and tarsi; all segments covered in faint grey mottling. Palp brown; embolus originating prolaterally, broad at base, initially directed distally, bending nearly 90 degrees retrolaterally before small bend at rounded tip, directed distally; RTA small, triangular in ventral view, with hooked tip in retrolateral view; several small denticles on dorsal surface of palpal tibia in retrolateral view; cymbium with two apophyses, ventral lobe round and flat, dorsal lobe hook-like, protruding in ventral view, with two distinct lobes ( Figs 214 , 230, 231 ).

Female (paratype, Hogsback, NMBA 16270). Measurements: CL 1.13, CW 0.97,AL1.25,AW 1.06, TL2.49, FL 0.06, SL 0.68, SW 0.55, AME-AME 0.03, AME-ALE 0.01, ALE-ALE 0.17, PME-PME 0.07, PME-PLE 0.10, PLE-PLE 0.35. Length of leg segments (sequence from femur to tarsus, and total): I 0.62 + 0.37 + 0.46 + 0.40 + 0.28 = 2.13; II 0.57 + 0.33 + 0.40 + 0.38 + 0.26 = 1.94; III 0.55 + 0.29 + 0.34 + 0.41 + 0.19 = 1.78; IV 0.68 + 0.29 + 0.52 + 0.51 + 0.24 = 2.24.

Carapace deep orange-brown, with faint black mottling ( Fig. 220 ); carapace granulate, more pronounced on lateral slopes, absent on posterior slope behind fovea; fovea short, indistinct, at Ō CL. AER slightly procurved; clypeus height approximately ¾ AME diameter; ALE slightly larger than AME; AME separated by distance slightly less than ½ their diameter; AME separated from ALE by distance less than ⅛ AME diameter, almost touching; PER strongly recurved; PLE slightly larger than PME; PME separated by distance equal to their diameter; PME separated from PLE by distance equal to 1⅓ times PME diameter. Chelicerae deep orange-brown, labium and endites pale orange-brown; sternum bright yellow-orange, orange-brown around borders. Abdomen oval, dorsum uniform creamy-grey ( Fig. 220 ); two pairs of indistinct oval sigilla, first pair at ¼ AL and second at midpoint of abdomen; venter creamy-grey. Legs uniform pale yellow-brown, with black mottling, leg I slightly darker; all patellae slightly paler than other segments. Epigyne with anterior copulatory openings in short recurved ridges; copulatory ducts short, directed mesally, entering globose ST II with finger-like posterior extension; connecting ducts of spermathecae almost parallel, running posteriorly either side of midline of epigyne, with short lateral branch entering dumbbell-shaped posterior ST I ( Figs 232, 233 ).

Type material. Holotype ♁: SOUTH AFRICA: Eastern Cape: Amatola Mountains, Hogsback, Arboretum , 32°35.305'S, 26°55.153'E, 22.III.2013, leg. C. Haddad, J. Neethling & R. du Preez (sifting leaf litter) ( NCA 2014 /378).

Paratypes: SOUTH AFRICA: Eastern Cape: Amatola mountains, Hogsback, Pine plantation, 32°35.508'S, 26°56.538'E, 1210 m a.s.l., 1.IV.2012, leg. C. Haddad & J. Neethling (canopy fogging 2, Podocarpus falcatus ), 9♁ 7♀ ( NMBA 16270 ), 1♁ 2♀ ( NCA 2014 /529); Same locality, Tyume Forest, 32°35.987'S, 26°55.880'E, 1140 m a.s.l., 3.IV.2012, leg. C. Haddad, J. Neethling, A. van Rooyen & R. du Preez (canopy fogging 7, Afromontane forest , Xymalos monospora ), 3♁ 1♀ ( NCA 2014 /517); Same locality, Tyume Forest , 32°35.960'S, 26°55.865'E, 1145 m a.s.l., 3.IV.2012, leg. C. Haddad, J. Neethling,A. van Rooyen & R. du Preez (canopy fogging 8, Afromontane forest , X. monospora ), 3♁ 1♀ ( NCA 2014 /457); Same locality, near Never Daunted Guest House, 32°35.770'S, 26°55.843'E, 1250 m a.s.l., 7.I.2010, leg. C. Haddad, C. Griswold & H. Wood (canopy fogging, exotic chestnut), 2♀ ( TMSA 23992 ) ; King William's Town State Forest , 32°58.331'S, 27°16.990'E, 450 m a.s.l., 29.XI.2013, leg. C. Haddad (beats, mixed forest), 1♁ 2♀ ( NCA 2013 /4338) .

Other material. SOUTH AFRICA: Eastern Cape: Amatola Mountains, Hogsback, Arboretum , 32°35.388'S, 26°56.123'E, 1200 m a.s.l., 26.III.2011, leg. C. Haddad, V. Swart, D. Fourie & R. du Preez (canopy fogging 1, P. falcatus ), 2♁ 3♀ ( TMSA 23997 ) ; Same locality, Arboretum, 32°35.283'S, 26°56.151'E, 1250 m a.s.l., 1.IV.2012, leg. C. Haddad & J. Neethling (canopy fogging, P. falcatus ), 5♁ 3♀ ( NCA 2014 /750); Same locality, Arboretum, 32°35.283'S, 26°56.151'E, 1250 m a.s.l., 2.IV.2012, leg. C. Haddad, J. Neethling, V. Swart & R. du Preez (canopy fogging, P. falcatus ), 1♁ 1♀ ( NCA 2014 /599); Same locality, Arboretum, 32°35.331'S, 26°56.115'E, 1250 m a.s.l., 3.IV.2012, leg. C. Haddad, J. Neethling, V. Swart, D. Fourie & R. du Preez (canopy fogging 5, P. falcatus ), 7♁ 4♀ ( NCA 2014 /864); Same locality, Arboretum, 32°35.356'S, 26°56.147'E, 1235 m a.s.l., 2.IV.2012, leg. C. Haddad, J. Neethling & R. du Preez (canopy fogging 6, Quercus sp. ), 8♁ 7♀ ( NCA 2014 /552); Same locality, Pine plantation, 32°35.519'S, 26°55.965'E, 1400 m a.s.l., 21.III.2013, leg. C. Haddad & R. du Preez (canopy fogging, Pinus radiata ), 4♁ 2♀ ( NCA 2014 /294); Same locality, Hobbiton Lodge, 32°36'S, 26°58'E, 6.IV.2010, leg. A.H. Kirk-Spriggs & V.R. Swart (malaise trap, Afromontane forest ), 1♁ ( NMBA 16723 ) ; Fort Fordyce Nature Reserve, 32°41.133'S, 26°29.875'E, 1090 m a.s.l., 30.XI.2013, leg. C. Haddad & J. Neethling (canopy fogging, Afromontane forest, mixed canopy), 1♁ 6♀ ( NCA 2013 /4417); Katberg State Forest , 32°28.220'S, 26°40.028'E, 1240 m a.s.l., 8.I.2011, leg. C. Haddad, C. Griswold & H. Wood (canopy fogging, indigenous forest), 6♁ 18♀ ( TMSA 23983 ) ; Mkambathi Nature Reserve, 31°16.399'S, 30°01.373'E, 10 m a.s.l., 27.I.2008, leg. III-UKZN (tree beats, forest, ECMF13), 1♁ ( NCA 2008 /2903); Same locality, 31°17.416'S, 29°59.415'E, 50 m a.s.l., 26.I.2008, leg. III-UKZN (tree beats, forest, ECMF-11), 1♁ ( NCA 2008 /2902); Suurberg Pass on R335, near Addo , 33°20.447'S, 25°45.028'E, 545 m a.s.l., 6.XII.2011, leg. J. Neethling & C. Luwes (canopy fogging, Afromontane forest ), 1♁ 3♀ ( NCA 2012 /1889) . KwaZulu-Natal: Oribi Gorge Nature Reserve, Samango Waterfall trail, 30°42.612'S, 30°16.182'E, 200 m a.s.l., 13.I.2011, leg. C. Haddad (canopy fogging, mixed forest trees), 1♀ ( TMSA 23985 ) .

Distribution. Widespread in the southern parts of the Eastern Cape and southern KwaZulu-Natal provinces, South Africa ( Fig. 236 ).

Figures

FIGURE 236. Distribution of Trachecymbius felis sp. nov. (blue circles), T. peterwebbi sp. nov. (green triangle) and T. tyume sp. nov. (yellow triangles) in southern Africa. Black star indicates Hogsback, where T. bosselaersi sp. nov., T. felis sp. nov., T. tyume sp. nov. and T. umbella sp. nov. occur sympatrically.

FIGURES 170–179. Digital microscope photographs of somatic morphology of Trachecymbius tyume sp. nov. male (170–174) and female (175–179). 170, 175. Habitus, dorsal view; 171, 176. Same, lateral view; 172, 177. Same, ventral view; 173, 178. Leg I, prolateral view; 174, 179. Metatarsus and tarsus IV. Scale bars = 1.0 mm (170–172, 175–177), 0.5 mm (173, 174, 178, 179).

FIGURES 180–188. Scanning electron micrographs of Trachecymbius tyume sp. nov. female (180, 182–188) and male (181). 180. Carapace, dorsal view; 181. Detail of carapace texture; 182. Eye region, dorsal view; 183. Same, anterior view; 184. Mouthparts; 185. Maxillar hair tuft and serrula; 186. Chelicerae, anterior view; 187. Sternum; 188. Femur I, retrolateral view.

FIGURES 198–203. Scanning electron micrographs of Trachecymbius tyume sp. nov. male. 198. Tibia I, lateral view; 199. Detail of ventral setae; 200. Metatarsus I, lateral view; 201. Detail of ventral setae, arrow indicating slit sensilla; 202. Tarsus I, lateral view; 203. Detail of ventral setae.

FIGURES 204–214. Scanning electron micrographs of Trachecymbius tyume sp. nov. female (204–212) and male (213, 214). 204. Metatarsus I, dorsolateral view; 205, 206. Metatarsus IV, ventral preening comb in prolateral (205) and ventral (206) views; 207–210. Tarsus I, prolateral view (207), showing details of claws (208), tarsal organ (209), trichobothrium base (210), with blackarrows indicating tarsal organ; 211. Epigyne; 212.Detail of anterior pockets, black arrow indicating copulatory opening; 213. Left palp, retrolateral-ventral view; 214. Detail of retrolateral and cymbial apophyses.

FIGURES 215–221. Digital microscope photographs of dorsal habitus of Trachecymbius spp. 215. T. bosselaersi sp. nov., female; 216, 217. T. felis sp. nov., male (216) and female (217); 218. T. peterwebbi sp. nov., male; 219, 220. T. tyume sp. nov., male (219) and female (220); 221. T. umbella sp. nov., female. Scale bars = 1.0 mm.

FIGURES 230–235. Trachecymbius tyume sp. nov., male (230, 231) and female (232, 233), and T. umbella sp. nov. female (234, 235): 230. Left palp, ventral view; 231. Same, retrolateral view; 232, 234. Epigynes, ventral view; 233, 235. Same, dorsal view. Scale bars = 0.1 mm.

FIGURES 189–197. Scanning electron micrographs of Trachecymbius felis sp. nov. male. 189. Carapace, dorsal view; 190. Eye region, dorsal view; 191. Mouthparts; 192. Detail of serrula; 193. Sternum; 194. Right palp, retrolateral view of patella, arrow indicating lyriform organ; 195. Same, retrolateral view of tibiae and tarsus; 196. Right palp, ventral view of tarsus; 197. Same, detail of embolus. Abbreviations: CA—cymbial apophyses; E—embolus; RTA—retrolateral tibial apophysis; TR—trichobothrium.