Zoosphaerium ambrense, Wesener, 2009

Wesener, Thomas, 2009, Unexplored richness: discovery of 31 new species of Giant Pill-Millipedes endemic to Madagascar, with a special emphasis on microendemism (Diplopoda, Sphaerotheriida), Zootaxa 2097 (1), pp. 1-134 : 84-86

Zoosphaerium ambrense , new species

Derivatio nominis: ambrense refers to the type locality, Montagne d'Ambre.

Studied material: 2 M, 2 F.

Holotype: 1 M (29 mm long), Geneve Mad 89/29. Locus typicus: Madagascar, Province Antsiranana, Parc National Montagne d'Ambre (=Ambohitra), vers le petit lac, foret primaire, 1010-1090 m, leg. C. Lienhard, 24.xi.1989.

Paratypes: 1 M, 2 F, Geneve Mad 89/29: same data as holotype .

Distribution: Known only from the rainforest of Montagne d'Ambre (Fig. 50)

Diagnosis: Medium sized, known specimens up to 34 mm long. Color (alternated by alcohol) completely light brown, tergites and antennae with traces of dark olive green. Collum and posterior margins of tergites with some short hair. First antennomere with groove, antennomeres 1–5 with sclerotized teeth (Fig. 57B), disc with four apical cones (Fig. 57A). First stigmatic plate with small, triangular lobe. Movable finger of posterior telopods weakly curved, length three times greater than width (Fig. 56D), with large, triangular lobe, and four thin spines (Fig. 56C), posterior side with 15–17 small sclerotized teeth (Fig. 56D). Fixed finger shorter than movable finger, reaching up to 3/4 of its length. Third podomere of anterior telopods on posterior side laterally with 1 or 2 small, isolated sclerotized teeth (Fig. 56B). One short stridulation rib on male harp (Fig. 56A) and three on each side of female washboard. Two locking carinae on anal shield, anterior one small, posterior carina three times larger than first. Operculum of vulva reaching up to apical coxal margin, medially notched, elongated into two small, well-rounded lobes. Lateral lobe slightly larger than inner one.

FIGURE 056. Zoosphaerium ambrense n. sp., holotype, A: right half of anterior telopods, anterior view; B: last two podomeres of anterior telopod, lateral view; C: posterior telopod, anterior view; D: chela of posterior telopod, posterior view. Abbreviation: IH = position of inner horns. Abbreviations: cav = cavity; cr-t = crenulated teeth; ml = membranous lobe; s-p = sclerotized spot; scl-t = sclerotized teeth; SR = stridulation rib. Scale bars = 1 mm.

Similar species: Zoosphaerium ambrense , n. sp. anterior and posterior telopods are of a shape not displayed among other known giant-pill millipede species (Figs 56A–D). The triangular lobe on the third podomere of the posterior telopods is quite similar to those of Zoosphaerium piligerum ( de Saussure & Zehntner, 1897) , but Z. ambrense , n. sp. differs from the latter in, among other characters, the general telopod shape.

Description: Body length: Males (2 specimens): length up to 29 mm, width of thoracic shield up to 14.1 mm, height of thoracic shield up to 7.8 mm. Females (2 specimens): length up to 34 mm, width up to 16.8 mm, height up to 9.4 mm. Too few specimens are known to evaluate if mature males are significantly smaller than mature females.

FIGURE 057. Zoosphaerium ambrense n. sp., paratype, SEM, A: antenna, apical view on disc; B: antenna, lateral view; C: right mandible, mesal view. Abbreviations: 3iT = 3 inner teeth; Co = condylus; eT = external tooth; mp = molar plate; pL = pectinate lamella.

Coloration: In most specimens faded by light and alcohol. In best preserved specimens, head, collum, thoracic shield, tergites, anal shield and legs light brownish, eyes and antenna with traces of green.

Head: Eyes with>60 ocelli.

Antennae: Length of antennomeres: 1=2=3>4<5<6 (Fig. 57B), sixth antennomere bearing disc with four apical cones (Fig. 57A). First antennomere of greatest width, with groove but without sensilla basiconica. Sclerotized teeth at base of antennomeres 1–5 (Fig. 57B).

Mandible: Six rows of pectinate lamellae, number of teeth declining apically to proximally (Fig. 57C). Molar plate with deep groove (Fig. 57C). Condylus damaged.

Gnathochilarium: Lateral of palpi circa five sensory cones, located together. Depression on posterior side of palpi with some sensory cones.

Collum: Whole surface of collum covered with few short, isolated hairs.

Thoracic shield: Texture similar to tergites.

Tergites: Shiny, at high magnification (90x) orange-peel like texture structure becomes visible. Paratergites projecting posteriorly.

Endotergum: Inner section with numerous short spines and long bristles. Between marginal ridge and inner area without cuticular impressions (Fig. 63D). Externally single row of marginal bristles. Bristles short, ending far before tergite margin (Fig. 63D).

Anal shield: Sexually dimorphic, in females well-rounded, neither bell-shaped nor tapered. In females glabrous. Ventral side of anal shield with two black locking carinae, located at ventral margin. Anterior carina short, running in 90 degrees angle upwards to anal shield margin. Posterior carina three times larger than first.

Legs: Tarsi of first pair of legs with six to eight, second with circa nine and third with circa 11 ventral spines. First two leg pairs with only weakly curved claws and without apical spine. Tarsi of legs 4–21 with curved claws, 10–12 ventral spines and one apical spine. Femur 2.0 and tarsi 3.6 times longer than wide.

Stigmatic plates: First lobe short and triangular, with rounded tip.

Female sexual characters: Subanal plate with washboard, consisting of large, broad and well developed stridulation ribs, with 2 or 3 ribs on each half. Vulva large, covering more than 3/4 of coxal surface. Operculum large, reaching up to apical margin. Apical margin of operculum medially notched, forming two, well-rounded processes, lateral part slightly larger than inner one. Mesal plate long, reaching up to 2/3 of operculum's height.

Male sexual characters: Anal shield almost rectangular with steep slope, covered by dense field short hairs, especially around hindmost point.

Anterior telopods (Figs 56A, B): Syncoxite glabrous, first podomere only with few isolated hairs. First podomere of rectangular shape, width 1.3 times larger than height, harp with one short rib. Second podomere process lobe-like and little curved with rounded edges, reaching up to 2/3 of third podomeres height, apically with sclerotized nubs. Third podomere cavity mesally in basal half with numerous small sclerotized spots, more apically with up to four thin, sclerotized spines; laterally with 1 or 2 minute sclerotized teeth. Third podomere apically with one round sclerotized spot. Podomeres 2 and 3 on both sides with isolated long hair.

Posterior telopods (Figs 56C, D): Third podomere elongated with well-rounded tip, length 3 times greater than width, only slightly tapering. Hollowed-out inner margin with one large, triangular lobe and four sclerotized spines, posterior aspect with 15–17 small, sclerotized teeth. Fixed finger straight, reaching only up to 3/4 of movable fingers length. Fixed finger not tapering, basally with single, short, sclerotized spine, apically covered with sclerotized spots. First podomere glabrous, second and third podomere covered on both sides with hair, especially at outer margins. Inner horns of syncoxite with pointed, slender tip.