Zoosphaerium sp.

Wesener, Thomas & Sierwald, Petra, 2005, New giant pill-millipede species from the littoral forest of Madagascar (Diplopoda, Sphaerotheriida, Zoosphaerium), Zootaxa 1097 (1), pp. 1-60 : 30-34

Zoosphaerium sp. from Sainte Luce

Figs 17–18

Material: 1f. (mature), 1f. (immature) coll. Madagascar, Province Toliara: Sainte Luce , littoral forest, 24°47’S 47°10’E; 08.IV.2003, leg. T. Wesener

Diagnosis: Splendid, black­colored pill millipede. Surface tergites 2–6 with a pattern of irregular, rounded sulci resembling roughened leather ( Fig. 16b ). Antennae with four sensory cones ( Fig. 17a ). Anal shield with two locking carinae, first punctiform, second 6 times longer ( Fig. 17b ). Concave lateral extension of the thoracic shield small, but marginal brim remarkably broad ( Fig. 16a ). Lateral extension and the depressions of paratergites white to yellowish. Vulvae small, covering only up to 2/3 of the coxa. Operculum of vulvae small, ending far before the apical edge of coxa ( Fig. 16e ). Males unknown.

Similar species: A comparison of this species with other Malagasy Sphaerotheriida species is very difficult, because males are missing. For this reason, no new species is described at this point. Drawings of the female are given for the comparison with other unsorted material, which may contain males of this undescribed species.

Description: Body length: 22.5 mm (mature female); width of thoracic shield: 11.2 mm (mature female); height of thoracic shield: 5.8 (mature female).

Habitus: posterior tergites higher than anterior ones ( Fig. 16a ).

Coloration: tergites shiny­black, smaller specimen blackish­white. Lateral extensions of thoracic shield and anterior paratergite depressions lighter, whitish to yellow in color. Antennae olive­green, legs and head light­brown.

Head: with numerous hairs and hair­pits especially around the labrum and laterally around the eyes. A few long hairs around the eyes and distributed on the entire head. Posterior margin of head towards the collum without a patch of short hairs. Head with up to 60 ocelli on each side.

A ntennae: shaped like in description of genus. Sixth antennomere longest, with 4 sensory cones ( Fig. 17a ). First antennomere much broader than the others.

Collum: Anterior margin with some isolated hairs arranged in a single row. Posterior margin with 4 hairs. Rest of collum hairless. Thoracic shield: marginal brim very broad ( Fig. 16a ). A few long hairs in the concave lateral extension of the thoracic shield. Concave lateral extensions small. Anterior paratergite depression of tergites 3–12 with some hairs, on the anterior margin of posterior tergites 1–2 ribs. Tips of the posterior margins of paratergites 8–12 projecting posterior. Tergites outside of the anterior paratergite depression bald, surface chagrined resembling roughened leather ( Fig. 16b )

Endotergum with one dense row of marginal bristles. Internal part with short spines and isolated bristles. Marginal ridge straight. Interior of marginal ridge one row of flat round cuticular impressions, each nodule isolated, far away from the next ( Fig. 17c ).

Anal shield: well­rounded, neither bell­shaped nor tapered ( Fig. 16a ). A few short, isolated (sensory?) hairs sparsely distributed over the entire surface of the anal shield. Ventral side carries two black locking carinae on both sides, anterior punctiform, posterior one more than six times longer than anterior one, at posterior end closer to the margin of the anal shield than at the anterior. Locking carinae separated from each other by a distance equal to the double length of the shorter anterior carina. Suture visible between locking carinae.

Legs: tarsi of first pair of legs with two, those of second with up to four ventral spines, weakly curved claws and without apical spine. Tarsi of legs 3–21 with curved claws, 10–12 ventral spines and one apical spine. 9th leg pair without coxal lobe ( Fig. 16c ). Coxae of all legs at the margins covered with many long hairs, the following leg joints with a few isolated, long hairs mostly around the margins. Femur with a black crenulated ridge ( Fig. 16c ).

Sternite: first sternite lobe broad and short, reaching above apical edge of the coxae of the first leg pair ( Fig. 16d ). Apical margin rounded regularly and covered with many long hairs. Inner margin of sternite curved. Sternites three and beyond with a spine­like process which reaches about the stigma opening of the anterior sternite.

Female sexual characters: second leg pair without coxal lobe ( Fig. 16e ). Vulvae small, covering up to 2/3 of the coxa. Operculum small, ending far before the apical edge of coxae. Apical margin of operculum slightly constricted in the middle (subreniform). Invagination dividing operculum irregular in two same sized parts, but no suture between the parts is visible. Both parts of operculum almost of same height. Basal margin straight. Exterior and inner plates (EP, IP) of vulva both surrounding the basal margin of the operculum. Inner plate very long and broad, reaching above the height of operculum. E xterior plate not as long as the inner one, reaching only the basal 1/3 part of the operculum. Cyphopod sclerites consisting of two triangular apical sclerites and a much larger third sclerite formed as a tuning­fork; all visible as dark structures near the suture of the vulva between inner and exterior plate ( Fig. 16e ). Subanal plate with washboard, consisting of regular symmetrical stridulation ribs. On each side 2–3 stridulation ribs, which are short, ending just above the middle of the subanal plate ( Fig. 16f ).

Ecology: This species was collected in wet leaf litter in the littoral forest fragment of Sainte Luce together with two other Sphaerotheriida , Zoosphaerium arborealis sp. nov. and Sphaeromimu s splendidus Wesener & Sierwald (in press). The niche separation of these three species is still unknown.

Conservation: This species was found only in the littoral forest fragment of Sainte Luce. Its survival is directly connected to the existence of the Sainte Luce littoral forest.

Figures

FIGURES 16 A–B: Z. villosum sp. nov., male paratype, SEM. a: left mandible, condylus; b: left mandible, pectinate lamellae.

FIGURES 17 A–F: Zoosphaerium sp. Sainte Luce, female. a: habitus; b: 5th paratergite; c: 9th left leg, posterior view; d: coxa and prefemur of 1st left leg with 1st left sternite; e: coxa of 2nd left leg with vulva, posterior view; f: subanal plate. EP = exterior plate, IP = inner plate, O = operculum, S = sternite. Scale bars = 1 mm.

FIGURES 18 A–C: Zoosphaerium sp. Sainte Luce, female; digital photo. a: tip of right antennae, b: left closing margins of anal shield, As = anal shield, 12T = 12th tergite, PM = locking carinae; c: endotergum, (1) = marginal ridge with external row of marginal bristles, (2) = band of flattened nodules, (3) = internal area. Scale bars = 1 mm