Thyropygus quadricuspis, Pimvichai, Piyatida, Enghoff, Henrik & Panha, Somsak, 2009

Pimvichai, Piyatida, Enghoff, Henrik & Panha, Somsak, 2009, A revision of the Thyropygus allevatus group. Part 2: the T. bifurcus subgroup (Diplopoda, Spirostreptida, Harpagophoridae), Zootaxa 2165, pp. 1-15 : 9-10

Thyropygus quadricuspis n. sp.

( Figs. 5 A–E, 7D)

Material: HOLOTYPE male THAILAND, Trang Province, Huai Yot district, Tam Khao Pina Temple, 7° 51ˏ 1˝ N, 99° 31ˏ 29˝ E. 14 January 2009. P. Pimvichai, C. Sutcharit and members of Animal Systematics Research Unit leg., ( CUMZ). – Paratypes: 2 males and 4 females, same data as holotype ( CUMZ), 2 males, 3 females, same data as holotype ( ZMUC).

Etymology: The species epithet is a noun in apposition and means “four prongs” and refers to the superficial similarity of the anterior gonopod to a four-pronged fish spear.

Diagnosis: A species of the bifurcus subgroup. Lateral margin of lateral process of anterior coxal fold (alp) with a small crest. Similar in this respect to T. bifurcus and T. demangei . Differs from these species by having a single femoral spine (fe).

Description: Adult males with 57–59 podous rings, no apodous rings. Length ca. 8–10 cm, width ca. 5.4–6.2 mm. Adult females with 57–61 podous rings, no apodous rings. Length ca. 8–10 cm, width ca.

6.2–6.8 mm. Overall color of living animal ( Fig. 7 D) brown, with a longitudinal yellowish brown band middorsally on the body; epiproct and paraprocts darker brown.

Gonopods ( Figs. 5 A–E): Anterior coxal fold (ac) ( Fig. 5 A): lateral process (alp) flattened, slightly curved, inflexed, with a lateral short sharp crest near tip ( Fig. 5 C, arrow); mesal process (amp) almost as long as alp, straight, directed distad. Posterior coxal fold (pc) ( Fig. 5 B) basally with moderately high lateral paracoxites (px), distally truncate, forming shelf (sh) for accommodation of telopodite, mesal process (pmp) slender, directed anteriad. Telopodite ( Figs. 5 D–E) leaving coxite over shelf of posterior coxal fold; femoral spine (fe) very long, slender, curved downward, with a small lamella at base of fe, in situ resting close to the middle part of alp; tibial spine (ti) long, slender, curving in horizontal plane, its tip in situ resting close to tip of amp; apical part: lamellar lobe (ll) broad, bent down; palette (pa) simple, gutter-like, with a longitudinal rounded crest (cr) near tip; distally with about eight brownish blepharochaetae (bp).

Distribution ( Fig. 8 ): Known only from the type locality.

Figures

FIGURE 5. Thyropygus quadricuspis, holotype, gonopods. A: anterior view, left telopodite removed. B: posterior view, left telopodite removed. C: lateral view. D: left telopodite, posterior-mesal view. E: left telopodite, anterior-lateral view.

FIGURE 8. Map of peninsular Thailand, showing the known distribution of the species of the T. bifurcus subgroup.

FIGURE 7. A: Thyropygus demangei, living male. B: Thyropygus enghoffi, living male. C: Thyropygus casjeekeli, living male. D: Thyropygus quadricuspis, living male. E: Thyropygus richardhoffmani, living male.