Medmassa sagax Tripathi, Kadam & Sankaran 2024, sp. nov.
Creators: name: Sankaran, Pradeep M.
name: Kadam, Gautam
name: Tripathi, Rishikesh
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Corinnidae
Medmassa
Medmassa sagax

description: Medmassa sagax Tripathi, Kadam & Sankaran sp. nov.
Figs 1A–B, D, G, 2–5, 8
Etymology. The specific epithet is an adjective and referring to the sharply pointed inner protuberance of the RTA of the new species (Fig. 5B–C). Latin sagax = sharp.
Type material. Holotype ♂ and paratype ♀ (ZSI/ WGRC /I. R.INV.26127 & 26128 respectively) from INDIA: Kerala: Kottayam: Kanjirappally: Mundakayam: HML Rubber estate (9°31’03.9’’N, 76°52’44’’E; 130 m a.s.l.), 7.V.2023, leg. R. Tripathi & G. Kadam, tree trunk, by hand.
Diagnosis. Males of M. sagax sp. nov. are most similar to those of M. torta Jin, H. Zhang & F. Zhang, 2019 by having a bifurcated RTA, well developed prolateral lobe of the tibia (as prolateral tibial tubercle in Jin et al. (2019)), and a very short embolus, but can be distinguished by the longitudinally narrow cymbium (vs. oval in M. torta), the tip of embolus blunt and directed at 1-o’clock in ventral view (vs. pointed and directed at 2-o’clock in M. torta), and the inner protuberance of the RTA short, with a prolaterally directed tip in ventral view (vs. comparatively long, with retrolaterally directed tip in M. torta) (cf. Figs 4A, B, D, 5A, B and Jin et al. 2019: figs 8E, F, 9A, B). Females are similar to those of M. celebensis (Deeleman-Reinhold, 1995), as both share roughly bean-shaped spermathecae that are in contact posteriorly, but can be separated by the copulatory openings being placed below the anterior margin of the spermathecae (vs. above the anterior margin of spermathecae in M. celebensis), and very short and straight copulatory ducts (vs. long and undulating in M. celebensis) (cf. Figs 4E–G, 5D, E and Deeleman-Reinhold 2001: fig. 541).
Description. Male in alcohol (Fig. 2). Carapace, eye region, clypeus, chilum, chelicerae, endites, labium, sternum, scutum brown; thoracic part with indistinct black blotches; leg segments yellow-brown to brown, distal half of all femora with black shade; dorsum, sides and anterior half of venter of opisthosoma black, posterior half of venter creamy white to yellow, dorsum medially with broad, longitudinal creamy white band; spinnerets creamy-white with black shade basally; anal tubercle creamy white; colulus black. Carapace sparsely covered with black setae; cephalic part squarish, thoracic part circular (Fig. 2A, D). Fovea short, straight, longitudinal (Fig. 2A). Chilum narrow, inverted triangular (Fig. 2C). Cheliceral boss prominent. Cheliceral promargin with three teeth, retromargin with four (Fig. 2E). Endites diverging, with distolateral hair tufts (Fig. 2F). Sternum rounded, rebordered, with weakly W-shaped anterior margin, covered with black setae (Fig. 2F). Opisthosoma oval, covered with fine appressed setae (Fig. 2A); anterior half of dorsum medially with scutum (Fig. 2A). Anterior tibiae with long paired ventral spines (Fig. 2G); all tarsi without scopulae, with claw tuft (Fig. 2G). Body length 6.54. Carapace 3.38 long, 3.28 wide. Opisthosoma 3.16 long, 2.33 wide. Eye sizes and interdistances: ALE 0.18, AME 0.30, PLE 0.23, PME 0.20; ALE–PLE 0.03, AME–ALE contiguous, AME–AME contiguous, AME–PME 0.10, PME–PLE 0.11, PME–PME 0.19. Clypeus height at AMEs 0.24, at ALEs 0.19. Chilum 0.05 long, 0.41 wide. Chelicerae 1.22 long. Length of palp and legs: palp 4.50 [1.55, 0.69, 0.76, 1.50], I 9.90 [2.98, 1.15, 2.69, 2.04, 1.04], II 9.77 [2.85, 1.15, 2.31, 2.26, 1.20], III 10.78 [2.96, 1.18, 2.32, 2.88, 1.44], IV 13.53 [3.35, 1.31, 2.82, 3.92, 2.13]. Leg formula: 4312. Spination of palp: femur pld 1 do 2, patella pl 1 pld 1, tibia pl 1 pld 2 plv 1 do 1 rlv 1, tarsus/cymbium spineless. Spination of legs: femur I pl 2 do 3, II pl 1 do 3, III pl 2 pld 1 do 3 rl 2 rld 1, IV pl 1 pld 3 do 3 rl 2; patellae I–IV spineless; tibia I plv 8 rlv 7, II pld 2 plv 6 rlv 5, III pl 3 plv 3 rlv 3, IV pl 2 plv 4 rl 2 rlv 3; metatarsus I plv 2 rlv 2, II plv 3 rlv 2, III pl 2 plv 2 rl 2 rlv 2 vt 1, IV pl 2 plv 2 rl 3 rlv 2 vt 1; tarsi I–IV spineless.
Palp (Figs 4A–D, 5A–C): cymbium dorsally with cymbial scopula, tip slightly narrowing towards anteriorly, ventrally with deep furrow reaching to anterior margin (Figs 4A–C, 5B). Prolateral lobe of tibia triangular (Figs 4A, 5A). RTA slender, with rounded tip, with short, claw-like inner protuberance (Figs 4B, C, 5B, C). Tegulum long, tear-shaped (Figs 4A–C, 5A–C). Subtegulum large, exposed prolaterally (Figs 4A, 5A). Sperm duct thick, U-shaped (Figs 4B, C, 5B, C). Embolus tiny, with blunt tip directed at 1-o’clock ventrally (Figs 4B–D, 5B, C).
Female in alcohol (Fig. 3). General aspects essentially as in male except for below: carapace, eye region, clypeus, chilum, chelicerae black-brown. Body length 6.91. Carapace 3.25 long, 2.95 wide. Opisthosoma 3.66 long, 2.50 wide. Eye diameters and interdistances: ALE 0.18, AME 0.26, PLE 0.19, PME 0.17; ALE–PLE 0.02, AME–AME 0.09, AME–PME 0.12, PME–PLE 0.13, PME–PME 0.19. Clypeus height at AMEs 0.21, at ALEs 0.15. Chilum 0.09 long, 0.52 wide. Chelicerae 1.30 long. Length of palp and legs: palp 4.33 [1.41, 0.68, 0.90, 1.34], I 9.03 [2.73, 1.25, 2.24, 1.81, 1.00], II 8.43 [2.50, 1.11, 2.00, 1.79, 1.03], III 9.14 [2.62, 1.05, 2.11, 2.35, 1.01], IV 10.79 [2.84, 1.15, 2.39, 2.90, 1.51]. Spination of palp: femur pld 1 do 2 v 3, patella pl 1 pld 1 do 1, tibia pl 2 plv 1 do 1 v 2, tarsus pld 1 plv 1 v 1. Spination of legs: femora I–II pl 1 pld 1 do 3, III pld 1 do 3 rl 3, IV pl 1 do 3; tibia II plv 6 rlv 5, III plv 2 rld 2 rlv 1, IV pl 1 pld 1 plv 2 rlv 1; metatarsus II plv 2 rlv 2, III pl 1 plv 2 rl 2 rlv 2 vt 1, IV rl 1 rld 2 rlv 2 vt 1.
Female genitalia (Figs 4E–G, 5D, E): epigynal plate triangular in shape, with convex posterior epigynal margin, medially with deep depression (Figs 4E, F, 5D). Copulatory openings small, separated from each other by about twice their diameter, lying just below anterior margin of spermathecae, with laterally thickened rim (Figs 4E, F, 5D). Copulatory ducts short, lying anterior to spermathecae, parallel to each other (Figs 4G, 5E). Spermathecae large, bean-shaped, contiguous posteriorly (Figs 4G, 5E). Fertilization ducts diverging (Fig. 5E).
Distribution. Known only from the type locality (Fig. 8).
description: Published as part of Sankaran, Pradeep M., Kadam, Gautam & Tripathi, Rishikesh, 2024, First records of Medmassa Simon, 1887 from India, with the description of two new species (Araneae: Corinnidae), pp. 133-143 in Zootaxa 5433 (1) on pages 134-138, DOI: 10.11646/zootaxa.5433.1.6, http://zenodo.org/record/10953699