Zoosphaerium ambatovaky, Wesener & Sagorny, 2021

Wesener, Thomas & Sagorny, Christina, 2021, Seven new giant pill-millipede species and numerous new records of the genus Zoosphaerium from Madagascar (Diplopoda, Sphaerotheriida, Arthrosphaeridae), European Journal of Taxonomy 758 (1), pp. 1-48 : 21-23

Zoosphaerium ambatovaky sp. nov.

urn:lsid:zoobank.org:act:42C1A931-D533-4FF6-B76A-CAB8F7E1461D

Figs 2C , 3 , 5C , 7

Diagnosis

The presence of only 7 or 8 ventral spines on the walking legs in Z. ambatovaky sp. nov., especially in combination with a glossy green color, two stridulation ribs on the male harp and more than 10 apical cones on the antenna, is only shared with Z. muscorum Wesener & Bespalova, 2010 . The new species differs from Z. muscorum in the presence of an apical spine on the third leg pair (absent in Z. muscorum ), the movable finger of the posterior telopod being 2.5 times as long as wide (2 times as long as wide in Z. muscorum ) and the second locking carina of the anal shield being 2–3 times as long as the first (4–5 times as long as the first in Z. muscorum ).

Etymology

‘Ambatovaky’, noun in apposition, after the forest of Ambatovaky, the only known locality for this species ( Fig. 3 ).

Material examined

Holotype MADAGASCAR – Toamasina • ♂; Rés. Speciale Ambatovaky , Sandrangato River ; 16°46′22″ S, 49°15′56″ E; alt. 450 m; rainforest; 20 Feb. 2010; B.L. Fisher et al. leg.; coll. no. BLF24311; CASENT 9068294 /1.

Description

Male

BODY LENGTH. Holotype male: length ca 44 mm, width of thoracic shield 23.1 mm, of tergite 5 24.4 mm (widest), height of thoracic shield 14.1 mm (highest).

COLORATION. Some discoloration may have occurred because of preservation in ethanol. Head, collum, thoracic shield and tergites shiny green with a conspicuous narrow light posterior margin ( Fig. 2C ). Anal shield of a different color, jade-like green. Antennae green, legs basally dark green, apically brownish.

HEAD. Eyes with> 95 ommatidia. Antennae long, with cylindrical joints, protruding posteriorly to leg pair 4. Length of antennomeres 1>2> 3=4= 5<6. A shallow groove present on antennomere 1. Male apical disc with 45/35 apical sensory cones. Organ of Tömösváry located in antennal groove.

GNATHOCHILARIUM AND MANDIBLE. Not dissected.

STIGMATIC PLATES. First stigmatic plate triangular, apex well rounded, nearly as wide as at base, slightly turned towards coxa. Hair most abundant on apical margin, very few hairs on basal and lateral margins ( Fig. 7C ).

PLEURITES. First pleurite well-rounded, not projecting.

COLLUM. Glabrous.

THORACIC SHIELD. Smooth and glabrous, without protuberances.

TERGITES. Surface glabrous and shiny, lacking small pits. Tips of paratergites of midbody tergites projecting posteriorly.

ENDOTERGUM. Inner section with numerous short triangular spines and longer setae. Middle area above spines with a single row of sparse circular cuticular impressions slightly varying in size. Apically with 1–2 rows of short marginal bristles, protruding to ⅔ of distance of tergite margin ( Fig. 5C ). Bristles with numerous small spines.

ANAL SHIELD. Male anal shield bell-shaped, without hairs, glabrous. Underside with two black locking carinae, posterior one 2–3 times as long as anterior one, both located close to anal shield margin.

LEGS. Leg 1 with 4 ventral spines, leg 2 with 6 or 7, leg 3 with 6. First two leg pairs without an apical spine, spine present on leg 3. Leg pairs 4–21 with 7 or 8 ventral spines and an apical spine. On leg 9, femur 2 and tarsus 4.5 times as long as wide. All podomeres with setae (Fig.).

Male sexual characters

GONOPORE. Covered with a single undivided, rounded membranous plate, covering ¼ of surface of coxa. Gonopore located on basal half of joint ( Fig. 7B ).

ANTERIOR TELOPODS. Harp with two stridulation ribs, one long and well pronounced rib located laterally of a less pronounced and shorter mesal rib ( Fig. 7D ). First podomere with only a few setae, restricted to apical parts of lateral margins, 1.5 times as wide as long. Process of second podomere nearly as long as basal ⅔ of third podomere, not visible in anterior view, and with an apical mound of a few sclerotized spots juxtaposed to third podomere ( Fig. 7E–F ). Third podomere with an apical brown sclerotized spot and a field of elevated sclerotized spots at inner margin below brown spot; two small spines located below sclerotized spot ( Fig. 7F ); depression lateral to field of spots with one small sclerotized spine, lateral margin with up to 6 crenulated teeth ( Fig. 7E–F ). Second podomere densely setose, third podomere with setae mainly apically and laterally.

POSTERIOR TELOPODS. Movable finger (podomere 3) 2.5 times as long as wide, weakly curved towards immovable finger (process of podomere 2). Shallowly hollowed-out inner margin with five sclerotized spines, three positioned apically and two in middle of cavity next to small membranous lobe. Additional sclerotized spine at base of movable finger. Posterior aspect with ca 12 small crenulated teeth ( Fig. 7H ). Immovable finger thinner and shorter than movable finger, curved towards the latter. Sclerotized spine located on anterior side near base of immovable finger. Inner part of immovable finger apically covered with a few sclerotized spots ( Fig. 7I ). Movable finger glabrous on both sides except for a few hairs basolaterally. Second podomere in posterior view setose, in anterior view with a few setae on finger.

Female

Unknown.

Distribution and ecology

Zoosphaerium ambatovaky sp. nov. is currently known only from the type locality, a lowland rainforest close to the Ille Sainte Marie ( Fig. 3 ). This species seems to be closely related to Z. muscorum from the montane forest of Anjanaharibe-Sud, the only species with which it shares the presence of only 7 or 8 ventral spines on the walking legs, as well as a glossy green color, two stridulation ribs on the male harp and more than 10 apical cones on the antenna. A female Zoosphaerium from the same forest (CASENT 9068291B) belongs to a different species. The forest of Ambatovaky is isolated and shrinking rapidly ( Rakotondrasoa et al. 2017).

Figures

Fig. 2. Habitus photographs of the seven new species of Zoosphaerium, lateral view. A. Zoosphaerium nigrum sp. nov., holotype (CASENT 9068289). B. Z. silens sp. nov., holotype (FMNH-INS 3119887). C. Z. ambatovaky sp. nov., holotype (CASENT 9068294/1).D. Z. beanka sp. nov., holotype (FMNH-INS 3119897). E. Z. voahangy sp. nov., holotype (FMNH-INS 3119921). F. Z. masoala sp. nov., holotype (FMNH-INS 3195651). G. Z. spinopiligerum sp. nov., holotype (FMNH-INS 3119885). Not to scale.

Fig. 3. Distribution map of the newly described species of Zoosphaerium. Vegetation color marks modified from Moat & Smith 2007. 1 = Z. nigrum sp. nov.; 2 = Z. silens sp. nov.; 3 = Z. ambatovaky sp. nov.; 4 = Z. beanka sp. nov.; 5 = Z. voahangy sp. nov.; 6 = Z. masoala sp. nov.; 7 = Z. spinopiligerum sp. nov. Numbers followed by ‘a’ mark additional, non-type localities.

Fig. 5. Scanning electron micrographs of the endoterga of midbody rings. A. Zoosphaerium nigrum sp. nov., holotype (CASENT 9068289). B. Z. silens sp. nov., holotype (FMNH-INS 3119887). C. Z. ambatovaky sp. nov., holotype (CASENT 9068294/1). D. Z. beanka sp. nov., holotype (FMNH- INS 3119897). E. Z. voahangy sp. nov., holotype (FMNH-INS 3119921). Scale bars = 100 µm.

Fig. 7. Zoosphaerium ambatovaky sp. nov., holotype (CASENT 9068291). A. Left leg 9, posterior view. B. Left coxa 2 with gonopore, posterior view. C. Left coxa 1 with stigmatic plate, posterior view. D. Left anterior gonopod, anterior view. E. Left anterior gonopod, posterior view. F. Left anterior gonopod, lateral view. G. Left female coxa 2 with vulva, posterior view. H. Female subanal plate with washboard. I. Right posterior telopod, posterior view. J. Right posterior telopod, anterior view. Abbreviations: as = apical spine; cl = claw; cr-t = crenulated teeth; cx = coxa; ep = external plate; fe = femur; gp = gonopore; ip = inner plate; o = operculum; pof = postfemur; pref = prefemur; s-ps = sclerotized spots; sr = stridulation rib; st = stigmatic plate; ta = tarsus; ti = tibia; vs = ventral spines. Roman numerals indicate telopoditomeres. Scale bars = 1 mm.