Desmoxytes pinnasquali Srisonchai, Enghoff & Panha, sp. n.

Desmoxytes pinnasquali Srisonchai, Enghoff & Panha sp. n.

(Figs. 1 G, 1H, 11–13)

Holotype. male (CUMZ) THAILAND, Phitsanulok Province, Noen Maprang District, near Pra Tham Mans Monastery (Tham Wangdaeng), 16º41'40"N, 100°40'42"E, ca 62 m a.s.l., 22 August 2014, leg. S. Panha, C. Sutcharit and U. Bantaowong.

Paratypes. 22 males, 5 females (CUMZ), 2 males, 1 female (ZMUC) same data with holotype; 10 males, 17 females (CUMZ) same locality together with holotype, 23 July 2008, leg. N. Likhitrakarn; 2 females (CUMZ) same locality together with holotype, 8 September 2009, leg. U. Bantaowong and R. Chanabun; 3 males, 6 females (CUMZ) THAILAND, Phitsanulok Province, Noen Maprang District, near Pa Ma Muang monastery, 16º34'00"N, 100°40'38"E, ca 92 m a.s.l., 23 July 2008, leg. C. Sutcharit and P. Tongkerd.

Etymology. The name is a Latin noun in apposition, meaning “shark fin” and referring to the shape of a process on lamina medialis.

Diagnosis. Metaterga with 2+2 anterior and 2+2 posterior spines, paraterga wing-like, shocking pink. Similar in these respect to D. planata, but differing by pink brown general body color, epiproct with digitiform apical papillae, sternal process between male coxae 4 being subquadrate, lamina medialis (lm) being highly elevated with a shark finlike process.

Descriptions. Length 24–29 mm (male), 28–30 mm (female); width of midbody prozona and metazona ca 2.0 and 2.0 mm (male), 2.2 and 2.5 mm (female).

Live coloration vivid pink; paraterga shocking pink; surface below below paraterga and metaterga brown pink; head and antenna dark brown; legs and epiproct pink; sterna brown (Figs. 1 G, 1H). Coloration in alcohol after one year faded to pale brown; paraterga, legs and sterna yellow brown; surface below paraterga, metaterga, head, antenna and epiproct brown.

Width of head <collum <segment 2 <3 = 4 <5–16, thereafter body gradually tapering towards telson. Head broad ca 2.0 mm (male), 2.5 mm (female). Clypeolabral region sparsely setose; vertex bare so on; labrum and genae sparsely setose; epicranial suture visible as dark line, quite deep (Figs. 13 A, 13D). Antennae very long and slender, reaching back to segments 5 (male) and 4 (female) when expanded dorsally (Fig. 13 D).

Collum width ca 3.0 mm (both sexes), surface coarsely microgranulate, with three transverse rows of small setiferous tubercles, 3(4)+3(4) anterior, 1+1 intermediate and 2+2 posterior tubercles; paraterga wing-shaped, elevated at about 30º (male) and 20º (female), directed dorsolaterad, tip pointed, with two distinct setiferous notches on anterior margin (Fig. 13 A).

Post-collum segments with surface of prozona finely shagreened; metazona coarsely microgranulate and shining; surface below paraterga finely microgranulate with inconspicuous wrinkles; paraterga and sterna quite smooth (Figs. 8 A–H, 13G). Suture between prozonae and metazonae conspicuous, quite deep and wide, narrow only in segments 2–5, thereafter much wider (Figs. 11 C, 11E, 13B, 13E, 13G). Metaterga with two transverse rows of setiferous spines; 2+2 anterior and 2+2 posterior spines; spines of anterior rows on metaterga 2–16 equal in size, lateral spines of posterior rows longer than mesal ones; metaterga 17–19 with all spines equal in size. Transverse sulcus on metaterga distinctly expressed on segments 5–17, quite deep, inconspicuous on segments 4 and 18, missing on segments 2, 3 and 19 (Figs. 11 A, 11C, 11F, 13A–C). Mid-dorsal line absent.

Paraterga strongly developed, especially in male, wing-shaped, directed dorsolaterad at ca 45º (Fig. 13 F), thereafter curving backward; shoulder present; calluses conspicuous, broad anteriorly and continuing slightly narrowed near tip; lateral margin with two distinct denticles, segments 9, 10, 12,13, 15–18 with an additional very small denticle near the tip (Fig. 13 H: arrow); tip of paraterga pointed and sharp, curving dorsolaterad; posterior margin of paraterga curving at base and almost straight near tip (Figs. 11 C, 11E, 13H). Ozopore (op) visible from above, ovoid (Figs. 11 C, 11E, 13H). Pleurosternal carinae forming complete crests on segment 2 (both sexes), small ridge on segment 3 and absent on following segments (Fig. 2 B).

Epiproct conical; tip concave; apical papillae conspicuous, digitiform; with tiny tubercles supporting two pairs of paramedian setae; lateral papillae distinct (Figs. 13 J–K). Hypoproct subsemicircular, with prominent setigerous tubercles on convex caudal margin (Fig. 13 I).

Sterna sparsely setose, cross-impression shallow; sternal process between male coxae 4 modified, subquadrate, tip round, sternal pores visible from posterior view (Figs. 11 G, 11H, 13M). Legs very long and slender, ca 2.5 (male), 2.0 times (female) as long as midbody height (Fig. 13 P). Male femora 5 and 6 distinctly humped ventrally in middle part, femur 6 a bit bigger than 5 (Figs. 11 I, 13N, 13O).

Gonopods (Figs. 12, 13 Q–T) long and slender, suberect, distal parts strongly condensed. Coxa (cx) about 1/3 as long as telopodite. Prefemorite (pfe) about 1/3 as long as telopodite, quite stout. Femorite (fe) slender, very elongate, with seminal groove running entirely on mesal surface, postfemoral part demarcated by deep mesal and lateral sulcus (Fig. 13 R: black & white arrows). Solenophore strongly developed: lamina lateralis (ll) swollen, without a lobe: lamina medialis (lm) broad and highly elevated, with one process and two lobes; process shark finlike, tip obtuse, directed mesad (Figs. 13 Q, 13S, P arrow); first lobe lamellalike, terminating in two lamellae, outer one smaller than the inner one (Figs. 13 Q, 13S, L1 arrow); second lobe lamellalike, thick and broad (Figs. 13 Q, 13S, L2 arrow). Solenomere flagelliform, curving distad.

Distribution and habitat. This new species occurs in a small limestone area in the west of Thung Salaeng Luang National Park, northern Thailand and was seen crawling on humid rocks, litter and vegetation under a shading tree.

Remark. This species shows a bizarre pink body color which is clearly aposematic. It may be closely related to D. planata with which it shares the same patterns of color and metatergal spines.