Scolopendra calcarata Porat, 1876

Siriwut, Warut, Edgecombe, Gregory D., Sutcharit, Chirasak, Tongkerd, Piyoros & Panha, Somsak, 2016, A taxonomic review of the centipede genus Scolopendra Linnaeus, 1758 (Scolopendromorpha, Scolopendridae) in mainland Southeast Asia, with description of a new species from Laos, ZooKeys 590, pp. 1-124 : 30-34

Taxon classification Animalia Scolopendromorpha Scolopendridae

Scolopendra calcarata Porat, 1876 Figs 9B, 25B, 29, 30, 31, 32, 33, 34, 35

Scolopendra calcarata Porat, 1876: 10. Haase 1887: 51. Attems 1930b: 33. Zhang 1992: 6, map 1. Schileyko 1995: 77, fig. 3, 1998: 268, 2001: 434, 2007: 74. Lewis 2010b: 98. Tran et al. 2013: 227.

Type locality.

China.

Material.

Holotype: NHRS-KASI 000000042, one female with label " Scolopendra calcarata v. Por" from Kina [China] in Kinberg collection (Figs 32, 33).

Additional material.

Thailand - CUMZ 00417, one spm., Wat Mae Long, Mae Chaem, Chiang Mai (18°13'42.315"N, 98°26'23.003"E). CUMZ 00418, one spm., Lan Sang Waterfall, Mueang, Tak (16°46'36.861"N, 99°0'39.441"E). CUMZ 00312, one spm., Chong Kao Khat (Hellfire Pass), Kanchanaburi (14°22'47.6"N, 98°55'47.7"E).

Diagnosis.

17 antennal articles, 4-6 basal articles glabrous dorsally. Each tooth-plate with 5-8 teeth. Tergites 3-20 with paramedian sutures. Complete margination only on tergite of ultimate leg-bearing segment. Tergite of ultimate leg-bearing segment without depression or median suture. Incomplete paramedian sutures on sternites. Coxopleural process with 3-4 apical, 0-3 subapical and 0-1 lateral spines, without dorsal spine. Ultimate leg prefemora with 4-12 VL, 0-12 VM, 1-5 M, 2 DM, prefemoral process with 3-5 spines. One tarsal spur on legs 1-21.

Composite description.

Body length up to 5.3 cm. Blackish colouration on most of dorsal part of body. Cephalic plate dichromatic; anterior part of cephalic plate dark blue or black, posterior margin green yellowish (Fig. 30B). Antenna dark blue. Tergites dark blue or nearly blackish. All legs light blue, their basal part yellowish. Cephalic plate with median sulcus on anterior part. Posterior part of cephalic plate without paramedian sulci.

Antenna usually with 17 articles, basal 4-6 subcylindrical, glabrous dorsally (Fig. 34C), 3.3 glabrous articles ventrally. Antenna reaching segments 3-4. Forcipular trochanteroprefemoral process with denticles in two groups, one apical and 2-3 inner. Tooth-plates with 5-8 teeth (Figs 30A, 34 A–B). Tooth-plate with straight, transverse basal suture. Coxosternite smooth, without median suture (Figs 30C, 34E). Article 2 of second maxillary telopodite with spur.

Anterior margin of T1 underlying cephalic plate (Figs 30B, 34C). Complete paramedian sutures from TT3-4; tergite margination only on T21 (starting on T15 in holotype). Tergite surfaces (Figs 31A, 34D) smooth, without median sulci. Tergite of ultimate leg-bearing segment with curved, acute posterior margin (Figs 31C, 35E), lacking median furrow or depression; ratio of width: length of tergite of ultimate leg-bearing segment 0.87:1. Sternites (Figs 31D, 35A) with incomplete paramedian sutures occupying anterior 10-30%. Surface of sternites smooth, without depression. Sternite of ultimate leg-bearing segment (Figs 31B, 35D) with sides converging posteriorly. Pore-field on coxopleuron terminating well beneath margin of tergite of ultimate leg-bearing segment, dorsal margin of pore area elevated equally along its length.

Coxopleural process moderately long, with 3-4 apical, 0-3 subapical and 0-1 lateral spines, without dorsal spine. Pore-free area extending 50-75% length from distal part of coxopleural process to margin of sternite of ultimate leg-bearing segment (Figs 31B, 35D).

All legs with small setae, without tibial spur. One tarsal spur on legs 1-21. Ultimate legs moderately long and slender, with ratios of lengths of prefemur and femur 1.2:1, femur and tibia 1.2:1, tibia and tarsus 2 1.4:1.; tarsus 1 and tarsus 2 2.6:1. Prefemoral spines (Figs 31 E–F, 35 B–C): 4-7 VL, 0-3 VM, 1-5 M, 1-7 DM, prefemoral process with 2-5 spines.

Genital segments well developed, reaching longer than distance between posterior margin of sternite of ultimate leg-bearing segment and distal part of coxopleural process. Sternite of genital segment 1 round and convex posteriorly, with median suture (Fig. 25B). In male, sternite of genital segment 2 well developed. Tergites of genital segments with small setae.

Discussion.

This montane species was sometimes collected together with other scolopendrids such as species of Otostigmus and Rhysida . External phenotypic characters are similar to Scolopendra pinguis but the unique, diagnostic character that permits species identification is the presence of a tarsal spur on the ultimate legs, which is atypical for Scolopendra . However, this character has been reported in some individuals of a few other Scolopendra species in Southeast Asia, notably Scolopendra subcrustalis (see Kronmüller 2009, Lewis 2010b). We also recorded the occurrence of a tarsal spur on the ultimate leg in two juveniles of Scolopendra subspinipes from Yokohama, Japan (NHMW 758). For this reason, variation in tarsal spurs on legs needs to be used cautiously for justification of species boundaries when sample size is limited. However, Scolopendra calcarata is readily distinguished morphologically from Scolopendra subspinipes s.l. and Scolopendra subcrustalis by the number of glabrous antennal articles (four glabrous dorsally), only the tergite of the ultimate leg-bearing segment showing margination, sternites with incomplete paramedian sutures, and 4-5 apical and subapical spines on the coxopleural process. All specimens from Thailand and the description of Vietnamese populations by Schileyko (1995) consistently exhibited a tarsal spur on the ultimate legs. However, some characteristics seem to be variable between these two populations, such as a count of six glabrous antennal articles in Vietnam versus four in Thailand (four in the original description), the last 4 -6 tergites marginated versus only the tergite of the ultimate leg-bearing segment (but in original description, margination starting from TT12 (13)), the sternite of the ultimate leg-bearing segment with a median depression versus its absence, and the arrangement of spines on the ultimate leg prefemur. With respect to the latter, Vietnamese populations exhibited 9-12 VL, 11-12 VM, 2-3 both M and DM, and 2 spines on the prefemoral process versus 4-7 VL, 0-3 VM, 1-2 M, 1-2 DM, and 2-4 spines on the prefemoral process in Thai populations.

Morphological similarity between Scolopendra calcarata and Scolopendra pinguis is indicated by several characteristics, including the number of antennal articles, the shape of teeth on the forcipular tooth-plates (these being in the form of minute denticles), and the number of spines on the coxopleural process. In addition, the habitat preferences of these two species resemble each other, both of them being found only in montane territory, and they also show similar dichromatic colouration patterns. There is no evidence from our survey that these two species are distributed sympatrically. These characters are consistent with the molecular phylogeny, which resolves these two species as sister taxa.

Distribution.

This species is quite rare in tropical mainland Southeast Asia, usually distributed along mountain ranges in the western territory of Thailand (Fig. 29). A few specimens were found in the eastern plateau. Schileyko (1995, 2007) also reported material from northern Vietnam, and Zhang (1992) recorded Scolopendra calcarata in southern China. We combine all records of this species from previous literature and our new collections to provide and updated distribution as follows: Southeast Asia: Thailand (Kanchanaburi, Tak and Chiang Mai) and Vietnam (fide Schileyko (2007): Mai Chau, Tam Dao National Park, Cat Ba National Park and Ba Vi National Park). East Asia: South China.