Sterropristes metallicus ( Verhoeff, 1937 )

Muadsub, Sawitree, Sutcharit, Chirasak, Pimvichai, Piyatida & Enghoff, Henrik, 2012, Revision of the rare centipede genus Sterropristes Attems, 1934, with description of a new species from Thailand (Chilopoda: Scolopendromorpha: Scolopendridae), Zootaxa 3484, pp. 35-52 : 39-46

Sterropristes metallicus ( Verhoeff, 1937)

( Figures 1 D–F, 2, 5, 6A, B, 7–9 and Table 1 )

Malaccolabis metallica Verhoeff, 1937: 202 , 203, pl. 12, figs 1–4. Type locality: Penang Hill, Penang, Malaysia.

Type material. The holotype was separately mounted on three glass slides. The first slide (catalogue number ZSM A20030951) contains the cephalic plate with antennae, first maxillae, second maxillae and mandibles ( Fig. 5 A, G–K). The second slide ( ZSM A20030952) contains the forcipules and segments 1 to 6 with their legs ( Fig. 5 B, C), unfortunately segments 7 to 17 seem to be lost. The third slide ( ZSM A20030953) contains segments 18 to 21 and the ultimate legs ( Fig. 5 D–F).

Topotype material. Penang Botanical Gardens, Penang, Malaysia (5o 26’ 8.9” N, 100o 17’ 34.2” E), CUMZ 3205, 8 January 2012. Penang Hill, Penang, Malaysia, CUMZ 3206, 9 January 2012. S. Muadsub and P. Pimvichai.

Descriptive notes on the holotype. The original description was well written by Verhoeff (1937). We here emphasize distinguishing characters, and characters not mentioned in the original description. Body length 43 mm. Left antenna with 12 and right antenna with 15 articles; articles 1 to 4 glabrous, articles 5 to the end very densely setose. Bases of coxosternal tooth plates meeting at a blunt angle, 4+4 coxosternal teeth, each tooth plate with two larger central teeth. Forcipular trochanteroprefemora without processes or teeth. Forcipular tarsungula nearly straight, internal margins with 13 saw teeth. Tergites 6 to 20 with paramedian sutures. Coxopleura longer than sternite of ultimate leg-bearing segment. Ultimate legs short and thickened; prefemora, femora and tibiae similar in length. Prefemora and femora length equal to width, tibiae longer than their widths, femora with short posterior dorsal grooves, tibiae prominently convex ventrally. Locomotory legs with scattered setae; leg 1 with one prefemoral, one femoral and two tibial spurs; leg 2 with two tibial spurs; legs 3 to 20 with only one tarsal spur.

Description of topotypes. Two topotypical specimens are available. They show some differences from the holotype but these variable characters are not sufficiently distinct to merit separate taxonomic status (differences with respect to numbers of teeth on the tarsungula appear to reflect an increase in teeth with increased body size). Length 18 and 28 mm ( Fig. 9 ). Colour in life dark to light purple. Antennae with 17 articles, the basal 4 with only a few short setae, articles 5 to 17 very densely setose ( Figs 7 A, C, 8A). Forcipular coxosternal tooth plates with 4+4 teeth. Forcipular tarsungula with 8 and 9 saw teeth ( Figs 7 B, C, 8A, B). Paramedian sutures starting on tergite 3 with short posterior sutures, tergites 4 to 5 with short anterior and posterior sutures, tergites 6 to 20 with complete sutures. Tergite of ultimate leg-bearing segment margined laterally, without posterior median depression, posterior margin slightly concave with obtuse angle in the middle ( Fig. 7 F). Paramedian sutures on sternites 4 to 12 incomplete; sternites 13 to 19 with complete sutures. Sternite of ultimate leg-bearing segment noticeably narrowed posteriorly, posterior margin concave, about 1/2 length of anterior margin. Coxopleura short and truncated, without spine, similar in length to sternite of ultimate leg-bearing segment ( Fig. 7 G). Locomotory legs 1 to 3 each with one tibial spur and two tarsal spurs, legs 4 to 20 each with one tarsal spur ( Fig. 8 C, D). Ultimate legs short and thickened; prefemora, femora and tibiae similar in length; dorsal sides of prefemora flattened, ventral sides without spines; femora with short posterior dorsal grooves; ventral sides of tibiae prominently convex ( Figs 7 F, G, 8F).

Remarks. We have examined the holotype of this species and found some incongruence with the original description. Verhoeff thus mentioned that legs 1 and 2 each have two tibial spurs, that legs 3 to 20 each have one tibial spur and that leg 1 has one prefemoral spur. However, we found that leg 1 has one prefemoral, one femoral and two tibial spurs ( Fig. 5 B), leg 2 has 2 tibial spurs and 2 tarsal spurs, and legs 3 to 20 have only one tarsal spur ( Fig. 5 C, D).

Sterropristes metallicus differs from S. sarasinorum by the latter species having more (seven versus four) sparsely setose antennal articles, posterior dorsal grooves on the ultimate legs being present on the prefemora and femora (instead of just on the femora), and the ventral sides of both tarsi with a prominent convex shape (as opposed to the tibiae in S. metallicus ).

Figures

FIGURE 1. Spiracles of segments 3, 5 and 7 (left to right, respectively). A – C. Holotype NMB 432 a of Sterropristes sarasinorum Attems, 1934. D – F. Specimen CUMZ 3205 of Sterropristes metallicus from Penang Botanical Gardens, Penang, Malaysia. G – I. Holotype CUMZ 3207 of Sterropristes violaceus Muadsub and Panha n. sp.

FIGURE 5. Holotype slide ZSM A 200309521 - 3 of Sterropristes metallicus (Verhoeff, 1937). A. Cephalic plate and antennae. B. Forcipular tarsungula and segments 1 and 2 C. Segments 5 and 6. D. Segments 19 to 21. E, F. Ultimate legs. G, H. Mandible. I. First maxilla. J, K. Second maxilla.

FIGURE 7. Specimen CUMZ 3205 of Sterropristes metallicus from Penang Botanical Gardens, Penang, Malaysia. A. Head and leg-bearing segments 1 to 5. B. Forcipules. C. Ventral view of head and sternites 1 to 5. D. Tergites 11 to 15. E. Sternites 11 to 15. F. Tergites 18 to 21 and ultimate legs showing convex underside of tibia. G. Sternite 18 to 21 and ultimate legs showing sternite of ultimate leg-bearing segment almost the same length as coxopleura.

FIGURE 8. Drawings of Sterropristes metallicus, CUMZ 3205. A. Antennae, head ventral and segment 1. B. Forcipules. C, D. Tergites 3 and 4 (C) and sternites 3 and 4 (D) showing transition from one tibial spur and two tarsal spurs on leg 3 to no tibial spur and one tarsal spur on leg 4. E. Sternite of ultimate leg-bearing segment almost the same length as coxopleura. F. Lateral view of ultimate legs with posterior femoral groove and convex underside of tibia.

FIGURE 9. Relationship between body length and number of tarsungula denticles of Sterropristes species.