Dolomedes karschi Strand, 1913

Sankaran, Pradeep M. & Kadam, Gautam, 2025, On the spider family Dolomedidae Simon, 1876 in India and Sri Lanka (Arachnida: Araneae), Zootaxa 5594 (2), pp. 258-268 : 259-260

Dolomedes karschi Strand, 1913

Figs 3–10

Dolomedes (Tarentuloides) karschi Strand, 1913: 121 (♂).

Type material. Holotype ♂ ( SMF4847-137 ), CEYLON (= SRI LANKA), 1874, leg. G. Worms, examined based on photographs.

Diagnosis. Males of D. karschi can be distinguished from the known males of Dolomedes species except D. mizhoanus by the combination of the following features: 1) a broad and thick RTA that fully surrounds the retrolateral side of palpal tibia; 2) a broad-based median apophysis with a ventrally folded base that forms a basal extension; 3) a DST with a retrolaterally extended posterior edge; 4) a long embolus that extends through the dorsal distal tegular projection; 5) a broad-based fulcrum drastically narrowed at its curved section; 6) an elongated lateral subterminal apophysis that can be observed retrolaterally without the expansion of the palp; and 7) chelicerae usually with more than three promarginal teeth ( Figs 7–9 ). Males of D. karschi can be separated from the males of D. mizhoanus by the anteriorly protruded RTA with three spines (vs. RTA flat with a single spine in D. mizhoanus ); by the triangular basal extension of the median apophysis (vs. thumb-shaped in D. mizhoanus ); and by the fulcrum with less protruded ventral edge (vs. more protruded in D. mizhoanus ) (cf. Figs 8–9 and Zhang et al. 2004: figs 21–22).

Redescription. Male in ethanol ( Figs 3–6 ). Carapace brown, laterally covered with dense, short, grayish setae ( Fig. 3 ); eye region red-brown, with sparse gray-brown setae; chelicerae dark yellow-brown, covered with long setae near fang furrow; endites, labium, and sternum yellow-brown; legs brown, covered with gray-brown setae, femur IV ventrally covered with extra dense long setae; dorsum of opisthosoma bearded with short, dark brown setae forming irregular brownish patches ( Fig. 3 ), anterolaterally with several lines of white setae, venter yellow-brown. Fovea distinct, longitudinal ( Fig. 3 ). Cheliceral promargin with five teeth, two large basal, and three small apical positioned close to central furrow, retromargin with four equal-sized teeth. Opisthosoma long-oval, with distinct cardiac mark ( Fig. 3 ). Body length 15.82. Carapace 8.74 long, 8.28 wide. Opisthosoma 7.08 long, 4.92 wide. Eye sizes and interdistances: ALE 0.26, AME 0.34, PLE 0.58, PME 0.52; AME–ALE 0.14, AME–AME 0.16, PME–PLE 0.48, PME–PME 0.24. Clypeus 1.25 long. Chelicerae 3.03 long. Length of palp and legs: palp 13.23 [5.40, 1.71, 2.51, 3.61], I 40.80 [11.02, 4.39, 10.89, 10.59, 5.67], II 40.80 [11.17, 3.23, 10.69, 10.14, 5.57], III 38.14 [10.59, 4.08, 9.25, 9.16, 5.06], IV 45.70 [11.69, 4.43, 11.14, 11.84, 6.60]. Leg formula: 4123. Palp ( Figs 7–9 ). Palpal tibia with a thumb-shaped ventral tibial apophysis and retrolaterally surrounded by a broad, highly sclerotised, and anteriorly protruded RTA with three sharp spines ( Figs 7–9 ). Basal retrolateral edge of the venter of cymbium with a long-oval basal cymbium apophysis ( Figs 8–9 ). Tegulum sclerotised, prolaterally attached to a large and elongated distal tegular projection, and retrolaterally to a long, membranous, and triangular conductor ( Figs 8–9 ). Subtegulum small, lying basomedial to the tegulum ( Fig. 8 ). Tegulum, distal tegular projection, and conductor form a U-shaped tegular ring having a highly sclerotised saddle that lies its lower center ( Fig. 8 ). Median apophysis hook-shaped, lying retrolaterally to the saddle, and is equally wide with a broad base; median apophysis basoretrolaterally with a triangular ventral fold ( Fig. 8 ). Fulcrum hook-shaped, with a very broad base, drastically shrinking at the curved region, with a folded ventral edge forming a groove containing the long, narrow, and curved embolus ( Figs 8–9 ). Lateral subterminal apophysis elongated with a rounded tip, visible retrolaterally without expanding the palp ( Fig. 9 ). Fulcrum, embolus, and lateral subterminal apophysis originated from distal sclerotised tube of apical division.

Variation. Unknown.

Female. Unknown.

Distribution. Sri Lanka (exact type locality unknown) ( Strand 1913) ( Fig. 31 ).

Figures

FIGURE 31. Currently known distribution records of the family Dolomedidae in India and Sri Lanka. ○ Dolomedes boiei (Doleschall, 1859) (doubtful record), ● Dolomedes karschi Strand, 1913, ▲ Dolomedes mizhoanus Kishida, 1936.

FIGURES 3–10. Dolomedes karschi Strand, 1913, holotype male. 3 Habitus, dorsal; 4 same, ventral; 5 same, retrolateral; 6 same, frontal. 7–9 Left palp: 7 prolateral; 8 ventral; 9 retrolateral. 10 Label associated with the specimen in the vial. Abbreviations: BCA, basal cymbium apophysis; C, conductor; DTP, distal tegular projection; E, embolus; F, fulcrum; LSA, lateral subterminal apophysis; MA, median apophysis; RTA, retrolateral tibial apophysis; S, saddle; ST, subtegulum; T, tegulum; VTA, ventral tibial apophysis. Scale bars: 3–6, 1 mm; 7–9, 0.1 mm. Photographs by Kuang-Ping Yu, © Senckenberg Research Institute, Frankfurt, Germany.