Otostigmus oatesi Kraepelin, 1903

Lewis, John G. E., 2014, A review of the orientalis group of the Otostigmus subgenus Otostigmus Porat, 1876 (Chilopoda: Scolopendromorpha: Scolopendridae), Zootaxa 3889 (3), pp. 388-413 : 403-404

Otostigmus oatesi Kraepelin, 1903

(Figs 45–49)

Otostigmus oatesi Kraepelin, 1903 , 120, Fig. 57 . Reef Island, Burma [ Myanmar]. O. (O.) oatesi: Attems, 1930 , 139.

O. oatesi: Khanna, 1994 , 464. Meghalaya, India.

Diagnosis. Length up to 42 mm. 17 antennal articles, the basal 2.25–2.66 glabrous. 4+4 forcipular coxosternal teeth, each an inner and outer group of two. Tergites without spinules, with complete paramedian sutures from 6–8, marginate from 8, 9 or 12. Sternites with short anterior paramedian sutures or none. Sternite of ultimate leg-bearing segment trapezoidal ratio of length to width from 0.93:1 to 1.1:1. Coxopleural process short, with two apical spines only. Two tarsal spurs on legs 1–4, to 19 with one. Ultimate leg prefemoral spines VL 2–3, VM 0–2 only (max 5).

Material examined. BMNH. Large tube labelled Otostigmus oatesii [sic!] Pocock Types (4) Burma: Tavoy, Reef Island Oates, E W. BMNH (E) 20072 Chilo 1889.7.15 and Ot. oatesii Poc. 8.9.7.15. Reef Island, Tavoy, two specimens (3 & 4) 41 mm and 31 mm. Ultimate legs missing. A smaller tube with two specimens (1 and 2) 33 and 30 mm and three loose ultimate legs, is labelled Reef Island (Tavoy). The specimens have many legs missing.

Description. (Kraepelin’s (1903) data in parentheses where relevant). Length 31–41 (42) mm. Antennae short, reaching segment 3 when reflexed, with 17 articles, the basal 2.25–2.66 glabrous.

Forcipular coxosternal teeth 4+4 (3, 3 or 4, 4), each an inner and outer group of two (Fig. 45). Trochanteroprefemoral process with two medial denticles.

Tergites smooth, without spinules, with complete paramedian sutures from 6 or 8 (7), marginate from 8, 9 or 12 (8 or 9). Sternites with short anterior paramedian sutures or none, with a median and two posterior lateral depressions in specimen 4 (with posterior median round pit and shallow elongated pit anteriorly). Sternite of ultimate leg-bearing segment with sides converging posteriorly, posterior margin rounded (Fig. 46), straight or slightly concave (Fig. 47) (shallowly emarginate), ratio of length to width 0.93:1 to 1.1:1. Coxopleural process short with two small apical spines but 2+ 1 in specimen 3 (one spined).

Leg 1with a femoral and tibial spur, 1–3 or 4 with two tarsal spurs, to 20 with one. Ultimate leg prefemoral spines VL 2, VM 1 (Fig.48), VL 3, VM 2 (Fig. 49) and VL 2, VM 0. M. DM and CS are absent in these three loose legs (almost without spines, only ventrolateral 1 (2), VM with an indistinct little bump).

Remarks. Although labelled as types by Pocock, the published description is by Kraepelin (1903). He certainly examined some of Pocock’s other species and his locality for oatesi (British Burma, Tavoy) is the same as that of the Pocock specimens. Otostigmus oatesi is not, as would be expected, on a list of the Otostigmus species in the Zoologisches Institut und Zoologisches Museum, Hamburg which was kindly supplied by Hieronymus Dastych (email dated 01.03.2004). I conclude that Kraepelin described Pocock’s material, albeit with some inaccuracies.

This examination of four specimens of O. oastesi shows that changes need to be made in the differential characters given by Attems (1930) in his key, as follows: coxopleuron typically two spined, not one spined; prefemur of ultimate leg spinulation more variable (see above); sternites with or without median depressions.

This species is clearly very closely related to O. orientalis . It is differentiated by relatively minor characters namely, coxopleural process short with two apical but consistently no lateral spine (always present in O.

orientalis ). Ultimate leg prefemoral spines VL 2–3, VM 0–2 (total 2, 3 or 5 only, 5 or 6 in O. orientalis ). It was recorded from India by Khanna (1994) but without any description.

Figures

FIGURES 55 – 62. Otostigmus striolatus. Syntypes. 55. Forcipular coxosternal tooth-plates ZMB spm. 56. Tergite 13 ZMB spm. (detail shown on left side only). 57. Sternite 16 ZMB spm. (partly freehand). 58. Ultimate leg-bearing segment ZMB spm. (detail of pores shown in posterior part of right coxopleuron). 59. Right coxopleural process ZSM spm. 60. Left coxopleural process ZSM spm. 61. Detached ultimate leg ZSM spm. 62. Second detached ultimate leg ZSM spm. FIGURES 63 – 67. Otostigmus sucki Syntypes. 63. Antennal article 3 dorsal spm. 2. 64. Right forcipular trochanteroprefemoral process and coxosternal tooth-plates spm. 3. 65. Ultimate tergite spm. 3. 66. Sternite of ultimate leg-bearing segment and left coxopleural process spm. 3. 67. Right prefemur ultimate leg spm 3 ventral. Scale bars = 1.0 mm except Figs 55, 58, 63 & 64 = 0.5 mm and Figs 59 & 60 = 0.1 mm.