Alluviobolus tsimelahy Wesener, 2009

Wesener, Thomas, Enghoff, Henrik & Sierwald, Petra, 2009, Review of the Spirobolida on Madagascar, with descriptions of twelve new genera, including three genera of ' fire millipedes' (Diplopoda), ZooKeys 19 (19), pp. 1-128 : 83-85

Alluviobolus tsimelahy Wesener , sp. n.

urn:lsid:zoobank.org:act:EA739EC9-0459-4440-891A-6D703BDE2FCC

Material examined: 14 ♂, 21 ♀, 47 imm. Holotype: 1 ♂ (42 mm long), FMMC W017 D, Madagascar, Province Toliara, RNI Andohahela, parcel II, Tsimelahy , gallery forest, in alluvial debris, 24°57.296’ S, 46°37.214’ E, leg. T. Wesener et al., 24.V.2007 . Paratypes: 4 ♂, 6 ♀, 6 imm., FMMC W017 D, same data as holotype ; 1 ♂, 1 ♀, 2 imm., CAS W017 D, same data as holotype ; 1 ♂, 1 ♀, ZMUC W017 D ; 1 ♂, 1 ♀, ZMH W017 D, same data as holotype .

Other material examined: 4 ♂, 4 ♀, 10 imm., W017D, same data as type material, but stored as vouchers at University Antananarivo ; 1 ♂, 4 ♀, 9 imm., FMMC W016 A, Andohahela mountain chain, Ebosika, rainforest, 24°56’45.24” S, 46°40’31.84” E, leg. T. Wesener et al., 15.VI.2007 ; 1 ♂, 4 ♀, 9 imm., W016A, same data as previous, University Antananarivo .

Differential diagnosis: see A. laticlavius for a differentiation of both taxa. It is possible that Ostinobolus rufus sp. n. can also be found in the Ebosika rainforest. Both species live in the same habitat and are of similar size and colour. O. rufus is, however, entirely red ( Fig. 48C ) while the mesozonites are dark olive greenish in Alluviobolus tsimelahy ( Fig. 42A ).

Description. Measurements: males with 47–49 body rings, circa 41–44 mm long, 3.6–4.3 mm wide. Females with 47–49 body rings, 52–60 mm long, 5.5–6.0 mm wide.

Coloration on mesozonites dark olive green, metazonites red ( Fig. 42A ). Rings dorsally with a slender orange stripe. Head, legs, antennae and telson red ( Figs 45 A–C). Eyes with 22–24 ocelli arranged in 4 or 5 rows ( Fig. 45A ). Antennae protruding back to ring 5 ( Fig. 45A ).

Male coxal processes on coxae 3–5 ( Fig. 45B ), 3 and 4 large, swollen, process on coxa 5 smaller ( Fig. 46B ). Preanal process absent ( Figs 45C , 46C ).

Anterior gonopod sternite elevated into a wide lobe, apically tapering. Tip wellrounded ( Fig. 45F ). Coxite and telopodite inconspicuous ( Fig. 45H ).

Posterior gonopods: telopodite with a membranous fringe ( Fig. 45I ). Apical sclerite (x in Fig. 45I ) slender, triangular, regularly protruding into a slender, acute tip ( Fig. 45G ).

Intraspecific variation: specimens from the rainforest of Ebosika show minute differences in the posterior gonopods towards those of the type series (compare Figs 45G, I with Figs 46J, L, M ). Ebosika specimens possess apically on the telopodite a short protruding process towards the membranous fringe ( Fig. 46L , marked with an arrow). However, size, number of body rings, colour pattern and the shape of male coxal processes ( Figs 46 A–C) are identical in specimens from both populations.

Distribution and ecology: A. tsimelahy is until now the only known Malagasy species of Spirobolida which occurs in the spiny forest and rainforest ecosystem, more precisely in the spiny forest at Tsimelahy and just 5 km east in the rainforest of Ebosika. The record from the spiny forest of Tsimelahy, however, is tainted, because the only place where Alluviobolus specimens were found was very close to the river, inside wet debris. It is currently unknown if the A. tsimelahy specimens from the spiny forest area represent a stable population or whether specimens just floated out of the rainforest and into the spiny forest during the wet season. It is perhaps not a coincident that the specimens from Ebosika were collected close to the same river as those in Tsimelahy ( Fig. 43 ).

Etymology: tsimelahy , noun in apposition, after the type locality.

Figures

Figure 42. Alluviobolus tsimelahy sp. n., A living male from Tsimelahy B male and female specimen from Ebosika.

Figure 43. Distribution map of the genus Alluviobolus gen. n.

Figure 45. Alluviobolus tsimelahy sp. n. A–C, F–I male holotype, D, E female paratype. A head, lateral view B legs 1–7, ventral view C telson D vulva and sterno-coxite of second leg, posterior view E left mandible, mesal view F anterior gonopod, anterior view G right posterior gonopod, anterior view H anterior gonopod, posterior view I right posterior gonopod, posterior view. 3iT = 3-combed internal tooth; Apo = apodeme; av = anal valves; Co = collum; Cx = coxite; eT = external tooth; Gn = gnathochilarium; LT = lateral tooth; Md = mandible; mp = molar plate; O = operculum; pL = pectinate lamella; Pre = preanal ring; pv = posterior valve; St = sternite; St-Cx = coxosternite; T = telopodite. Scale bars = 1 mm.

Figure 46. Alluviobolus tsimelahy sp. n. specimens from Ebosika, A–G, I–M male, H female. A head, lateral view B legs 1–7, ventral view C telson D gnathochilarium, ventral view E gnathochilarium, mentum F gnathochilarium, dorsal view on endochilarium G, H left midbody legs I anterior gonopod, anterior view Į right posterior gonopod, anterior view K anterior gonopod, posterior view L right posterior gonopod, telopodite, posterior view M right posterior gonopods, coxite and sternite, posterior view. Apo = apodeme; av = anal valves; Co = collum; cp = central pads; Cx = coxite; Endo = endochilarium; Gn = gnathochilarium; L = ledge; Md = mandible; Me = mentum; Pre = preanal ring; St = sternite; ST = stipites; sub = subanal scale; T = telopodite. Scale bars = 1 mm.

Figure 48. Ostinobolus rufus sp. n., A, B, D, G–J male holotype; C, E, F male paratype. A head, lateral view B legs 1–7, ventral view C living specimen D telson E gnathochilarium F midbody ring with leg G anterior gonopod, anterior view H anterior gonopod, posterior view I left posterior gonopod, anterior view Į left posterior gonopod, posterior view. Apo = apodeme; av = anal valves; Co = collum; Cx = coxite; Gn = gnathochilarium; L = ledge; Md = mandible; Pre = preanal ring; St = sternite; sub = subanal scale; T = telopodite. Scale bars = 1 mm.