Digitipes coonoorensis Jangi and Dass, 1984

Joshi, Jahnavi & Edgecombe, Gregory D., 2013, Revision of the scolopendrid centipede Digitipes Attems, 1930, from India (Chilopoda: Scolopendromorpha): reconciling molecular and morphological estimates of species diversity, Zootaxa 3626 (1), pp. 99-145 : 105-108

Digitipes coonoorensis Jangi and Dass, 1984

( Figs 13–23 )

Digitipes coonoorensis Jangi and Dass, 1984: 43 , figs 62–72. Digitipes coonoorensis . Sureshan et al. 2006: 2287.

Digitipes putative species 1. Joshi and Karanth, 2012: figs 2, 3, 5.

Diagnosis. Digitipes with basal three antennal articles glabrous dorsally. Tergite paramedian sutures complete from TT6 to 8; tergites fully marginate starting from 7 to 9; tergites smooth, longitudinal median ridge rarely present. Coxopleural process relatively long, stout, variably inflected outward in ventral view, lateral spine present; pore field terminating far beneath dorsal margin of coxopleuron; leg 20 without tarsal spur.

Material examined. 11 specimens of Digitipes putative species 1 ( D. coonoorensis of Joshi and Karanth, 2012), including CES07125, CES07132 and CES07134 from close to type locality; CES registration numbers in Joshi and Karanth (2012: fig. 2, Table S1). These individuals were collected largely in high elevation forests (<1800 msl) of the southern and central parts of the Western Ghats, India (distribution map in Joshi and Karanth 2012: fig. 5c); all leg. J. Joshi, 2007–2010.

Description. Length to 64 mm. 17 antennal articles, 18 on one side in one individual in which abnormally short distal articles suggest damage; basal three articles glabrous dorsally ( Fig. 13 ), 2.3–2.5 articles glabrous ventrally. Cephalic plate and tergites finely punctate. Longitudinal median furrow 15–20% length of cephalic plate.

Colour variable: cephalic plate, basal (glabrous) part of antennae and T1 often blue; trunk may display gradual increase in brown pigment posteriorly, sometimes reverting to blue in posterior tergites; exceptionally cephalic plate and tergites all brown, or most of head and T1 brown with mostly blue tergites from T2; legs pale blue-brown.

Forcipular coxosternal tooth plate wider than long ( Figs 14, 15 ), with four main teeth, the inner two usually grouped, the outer tooth smaller than the inner three ( Fig. 15 ); bases of tooth plates defined by oblique sutures diverging at a relatively obtuse angle of 140–150°. Trochanteroprefemoral process with two distinct teeth along inner margin.

Second maxillary claw with slender, needle-like accessory spurs. Article 2 of telopodite bearing a long, slender, pigmented spine distally.

Tergites with paramedian sutures complete from TT6 to 8. Tergites marginate from 7, 8 or 9. Tergites smooth ( Fig. 22 ), longitudinal median ridge mostly absent, faint from T 9 in CES08960. Sternites usually with short paramedian sutures, ca 10% length of sternites in mid body region, at most about 25% length of sternites, sometimes with a short extent on posterior part of sternite.

Spiracle of segment 3 with narrow elliptical outline ( Fig. 23 ), long axis oblique to horizontal plane; spiracles from segment 5 with rounded outline, irregular inner margin of peritrema, long axis of spiracular opening vertical. All spiracles with regularly scalloped inner margin of peritrema, folding into a smooth band of trichomes beneath which atrium has strongly humped wall and floor.

First three (four in one individual) pairs of legs with two tarsal spurs, the subsequent up to 19 with one. Leg 20 without tarsal spur, except one individual. A tibial and a femoral spur on leg 1 only.

Tergite of ultimate leg-bearing segment with gently convex lateral margins that weakly converge posteriorly; posterior margin gently sinuous, bluntly pointed to rounded posteromedially ( Fig. 17 ). Sternite of ultimate legbearing segment with sides converging posteriorly, nearly straight, posterior margin moderately concave ( Fig. 18 ).

Coxopleural process moderately long, robustly conical, set off from course of posterolateral margin of coxopleuron by a pronounced inflection, its apex variably with a slight to distinct lateral orientation ( Fig. 18 ); two apical spines, one lateral spine (absent on one side in two individuals). Coxopleural pores relatively dense, approximately bimodal size distribution; pore field relatively narrow, terminating moderately to strongly beneath dorsal margin of coxopleuron ( Fig. 16 ); non-porose area on coxopleural process at least 60% length to posterior margin of sternite of ultimate leg-bearing segment, sometimes nearly reaching that margin ( Fig. 18 ). Ultimate leg prefemur with width at distal end about 30% its length. Prefemoral spines moderately large ( Fig. 19 ): VL 3 (small fourth spine rarely present), VM 2 (one specimen with 3 on one side), DM 0 or 1. Distomedial process in males bluntly conical, extending about as far as the distal end of the femur on its dorsal side ( Fig. 20 ); groove on medial surface of femur extending about half length of femur ( Fig. 21 ). Ultimate leg tarsus 1 1.6–2.5 times length of tarsus 2; tarsus 1 2.2–5 times longer than pretarsus; pretarsus with pair of short accessory claws.

Discussion. Absence of a leg 20 tarsal spur was used by Jangi and Dass (1984: 41) in the first couplet of their key to Indian species of Digitipes , allowing D. coonoorensis (spur absent) to be distinguished from D. barnabasi and D. indicus (spur present). We observe this character to remain reliable for separation of D. coonoorensis apart from one individual resolved within the species phylogenetically that possesses a spur.

A record of D. coonoorensis was made by Yadav (1993b: 324) from Sindhudurg, Maharashtra, more northerly than any material of the species examined by us. We have not seen the material and have not included the record in the synonymy. All the individuals examined here were found in the shola forests or grasslands of high elevation areas of the southern Western Ghats.

Light-microscopic description of the spiracles is included for this species. For comparative purposes, the spiracle on segment 3 is depicted for other species of the genus as well ( Figs 40, 45 , 56 , 67 ), but we have not identified obvious taxonomic variation.

Figures

FIGURES 13 – 18. Digitipes coonoorensis Jangi and Dass, 1984. CES 08960 (female) except Fig. 15, CES 07125 (female) and Fig. 16, CES 091088 (male). 13. Cephalic plate and T 1, dorsal view, scale = 1 mm. 14. Forcipular segment, ventral view, scale = 1 mm. 15. Tooth plates, ventral view, scale = 1 mm. 16. Coxopleuron, lateral view, scale = 1 mm. 17. Tergite of ultimate legbearing segment, dorsal view, scale = 0.5 mm. 18. Coxopleuron and sternite of ultimate leg-bearing segment, ventral view, scale = 0.5 mm.

FIGURES 19 – 23. Digitipes coonoorensis Jangi and Dass, 1984. 19. Ultimate leg prefemur, ventral view, CES 08960 (female), scale = 0.5 mm. 20. Ultimate leg femur, dorsal view, CES 091088 (male), scale = 0.5 mm. 21. Ultimate leg femur, medial view, CES 091088, scale = 0.5 mm. 22. TT 18 – 20, dorsal view, CES 08960, scale = 1 mm. 23. Spiracle on segment 3, CES 07125, scale = 0.25 mm.

FIGURES 36 – 45. Digitipes jonesii (Verhoeff, 1938). 36 – 40, CES 091062 (male); 41 – 45, CES 091090 (male). 36. Ultimate leg prefemur, ventral view, scale = 1 mm. 37. Ultimate leg femur, dorsal view, scale = 1 mm. 38. Ultimate leg femur, medial view, scale = 1 mm. 39. TT 18 – 19, dorsal view, scale = 1 mm. 40. Spiracle on segment 3, lateral view, scale = 0.5 mm. 41. Ultimate leg prefemur, ventral view, scale = 0.5 mm. 42. Ultimate leg femur, medial view, scale = 0.5 mm. 43. Ultimate leg femur, ventral view, scale = 1 mm. 44. TT 18 – 20, dorsal view, scale = 1 mm. 45. Spiracle on segment 3, lateral view, scale = 0.25 mm.

FIGURES 52 – 56. Digitipes jangii n. sp. CES 08912 (holotype male) except Fig. 56, CES 08915 (paratype male). 52. Ultimate leg prefemur, ventral view, scale = 0.5 mm. 53. Ultimate leg femur, dorsal view, scale = 0.5 mm. 54. Ultimate leg femur, medial view, scale = 0.5 mm. 55. TT 18 – 20, dorsal view, scale = 0.5 mm. 56. Spiracle on segment 3, scale = 0.25 mm.

FIGURES 63 – 67. Digitipes periyarensis n. sp. Holotype CES 091037 (female) except Fig. 63, CES 091038 (female). 63. Ultimate leg prefemur, ventral view, scale = 0.5 mm. 64. Ultimate leg, dorsal view, scale = 1 mm. 65. Ultimate leg femur and tibia, dorsal view, scale = 0.5 mm. 66. TT 18 – 20, dorsal view, scale = 1 mm. 67. Spiracle on segment 3, lateral view, scale = 0.25 mm.