Zoosphaerium spinopiligerum, 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 : 34-37

Zoosphaerium spinopiligerum sp. nov.

urn:lsid:zoobank.org:act:B5E6A6B0-F750-4227-8F0B-4F6417FDF88D

Figs 2G , 3 , 10B , 12

Diagnosis

The greatly elongated posterior telopods identify Zoosphaerium spinopiligerum sp. nov. as a member of the Z. piligerum species-group. Zoosphaerium spinopiligerum sp. nov. shares the shape of the vulva and the anal shield, as well as a similar posterior telopod with Z. pseudopiligerum . Zoosphaerium spinopiligerum sp. nov. differs from the latter in the non-glossy tergites, differences in the shape of the anterior telopods, as well as the higher number of ventral spines on the legs (see key above).

Etymology

‘Spinopiligerum’, noun in apposition, as a reference to the higher number of ventral spines on the legs compared to related species.

Material examined

Holotype MADAGASCAR – Fianarantsoa • ♂; Parc National de Midongy-Befotaka , 6 km N of Befotaka village; 23°46.7′ S, 47°06.4′ E; alt. 815 m; dense humid transitional lowland and montane forest; 8 Feb. 2008; V. Soarimalala leg.; coll. no. VS-1442; FMNH-INS 3119885 .

Other material

MADAGASCAR – Fianarantsoa • 1 ♀; Parc National de Midongy-Befotaka , 11.5 km SW of Befotaka village; 23°53.3′ S, 46°53.3′ E; alt. 1053 m; dense humid transitional lowland and montane forest; 27 Feb. 2008; V. Soarimalala leg.; coll. no. VS-1536; FMNH-INS 3119888 .

Description

BODY LENGTH. Male: length 37.1 mm, width of thoracic shield 22.3 mm (widest), height of thoracic shield 11.1 mm (highest). Female (paratype): length 28.8 mm, width of thoracic shield 16.8 mm, height of thoracic shield up to 8.7 mm.

COLORATION. Tergites brown with dark brown posterior margin ( Fig. 2G ). Collum dark brown to green. Head dark green with yellow-brown markings. Anal shield brown. Antennae dark green, legs basally light brown, apically dark green.

HEAD. Eyes with more than 80 ommatidia. Antennae long and slender, protruding back to leg 3. Length of antennomeres 1 =2= 3=4 =5<6. A shallow groove present on antennomere 1, disc with 22/18 apical cones.

GNATHOCHILARIUM AND MANDIBLE. Not dissected.

STIGMATIC PLATES. First stigmatic plate lobular, apex well rounded, very slightly curved towards coxa. Hairs most abundant on apical margin ( Fig. 12C ).

PLEURITES. First pleurite slightly extending posteriorly in a long, thin process.

COLLUM. Median part of collum glabrous.

THORACIC SHIELD. Surface similar to that of tergites.

TERGITES. Paratergites slightly projecting posteriorly. Tergites covered with small pits and hairs.

ENDOTERGUM.Inner section with numerous short spines and isolated bristles. Between marginal ridge and inner area a single row of sparse large, elliptical cuticular impressions, distance between impressions 2–3 times as large as their diameter. Marginal brim wavy towards inner area. Externally with 1 row of sparse marginal bristles. Bristles scaly, short, the longest reaching ⅓ of distance towards tergite margin ( Fig. 10B ).

ANAL SHIELD. Rounded, slightly flattened in male, covered with numerous short setae. Ventral side of anal shield with two black locking carinae, located close to laterotergites.Anterior carina small, posterior carina 6 or 7 times as long as anterior carina.

LEGS. Leg 1 with 5 ventral spines, leg 2 with 6, leg 3 with 8. First two leg pairs without an apical spine, spine present on leg 3. Leg pairs 4–21 with 10–12 ventral spines and an apical spine. On leg 9, femur 2.1 and tarsus 5.2 times as long as wide. All podomeres with setae ( Fig. 12A ).

Male sexual characters

GONOPORE. Covered with a single undivided, rounded, apically membranous, basally sclerotized plate, covering ¼ of surface of coxa. Gonopore located basally on joint ( Fig. 12B ).

ANTERIOR TELOPODS. Harp with two stridulation ribs, both ribs of same size and well developed, located in mesal corner ( Fig. 12D ). First podomere 1.3 times as wide as long. Second podomere process lobe- like and slightly curved, with rounded edges, protruding up to ⅔ of third podomere height, apically with sclerotized spots, visible in anterior view ( Fig. 12D–F ). Third podomere narrow, half as long as first; cavity mesally with numerous sclerotized spots and three thin, sclerotized spines ( Fig. 12E–F ); one sclerotized spot located close to tip; laterally with up to 4 crenulated teeth. Podomeres 1–3 on both sides with numerous long, isolated hairs.

POSTERIOR TELOPODS (FIGS). Movable finger strongly curved, apically with invagination. Hollowed-out inner margin with one large triangular membranous lobe and 3–5 smaller sclerotized spines ( Fig. 12H ). Posterior aspect of movable finger with ca 11 small, sclerotized teeth ( Fig. 12I ). Immovable finger slender, with weakly curved tip, slightly shorter than movable finger. Anterior side of immovable finger basally with a membranous lobe and a sclerotized spine, at tip with numerous small sclerotized spots ( Fig. 12I ). All three podomeres of posterior telopods on both sides glabrous. Inner horns of syncoxite apically curved posteriorly. Tips sharp, entire horns covered with numerous short hairs.

Female sexual characters

Subanal plate wide, slightly triangular. Washboard with well-developed stridulation ribs, with 3 ribs on each half ( Fig. 12G ). Vulva large, covering more than ⅔ of coxa ( Fig. 12J ). Operculum small and low, ending far before coxal margin. Apical margin of operculum medially notched, lateral tip twice as high as mesal one, well rounded. Mesal plate long, extending beyond operculum.

Distribution and ecology

Zoosphaerium spinopiligerum sp. nov. occurs in sympatry with Z. nigrum sp. nov. and Sphaeromimus midongy Moritz & Wesener, 2017 in the remote mountainous forests of Midongy in the southeast of Madagascar ( Fig. 3 ).

Remarks

The female specimen examined here is only tentatively placed in Z. spinopiligerum sp. nov. as its COI barcode shows quite a p-distance to the male holotype ( Table 2 ). Such a distance is far higher than usually present in millipedes.

New locality data for Zoosphaerium species in Madagascar

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. 10. Scanning electron micrographs of the endoterga of midbody rings. A. Zoosphaerium masoala sp. nov., holotype (FMNH-INS 3195651). B. Z. spinopiligerum sp. nov., holotype (FMNH-INS 3119885). Scale bars = 100 µm.

Fig. 12. Zoosphaerium spinopiligerum sp. nov., holotype (FMNH-INS 3119885). A. Right leg 9, posterior view. B. Left coxa 2 with gonopore, posterior view. C. Right coxa 1 with stigmatic plate, posterior view. D. Left anterior gonopod, anterior view. E. Left anterior gonopod, lateral view. F. Left anterior gonopod, posterior view. G. Female subanal plate with washboard. H. Right posterior telopod, posterior view. I. Right posterior telopod, anterior view. J. Left female coxa 2 with vulva, posterior 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; syn = syncoxite; ta = tarsus; ti = tibia; vs = ventral spines. Roman numerals indicate telopoditomeres. Scale bars = 1 mm.