Zoosphaerium corystoides, 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 : 66-70

Zoosphaerium corystoides , new species

Derivatio nominis: corystoides , adjective, refers to the anal shield shaped like a helmet.

Studied material: 31 M, 4 F.

Holotype: 1 M (27 mm long), FMMC 3932 . Locus typicus: Madagascar, Province Antsiranana, Parc National Montagne d'Ambre , 3.6 km 235° SW Joffreville, montane rainforest, 925 m, 12°32'4"S, 49°10'46"E, coll. Fisher, Griswold et al., 20–26.i.2001, pitfall trap.

Paratypes: 27 M, 3 F, FMMC 3932 , same data as holotype . 3 M, 1 F, CAS BLF 2782 , Parc National Montagne d'Ambre , 12.2 km 211° SSW Joffreville, montane rainforest, 1300 m, 12°35'47"S, 49°9'34"E, coll. Fisher, Griswold et al., 2–7.i.2001, pitfall trap .

Distribution: Known only from the montane rainforest of Montagne d'Ambre, Northern Madagascar (Fig. 38).

Diagnosis: Medium sized, up to 33 mm long, males slightly (circa 5 mm) smaller than females. Color shiny black with red antennae and legs. Anal shield huge and prominent, in both sexes covered anteriorly with dense field of minute hair. Lateral excavations of thoracic shield deep and wide. First antennomere with groove, antennomeres 1–3 with sclerotized teeth (Fig. 46A), disc with 17–32 apical cones (Fig. 46B). Movable finger of posterior telopods slender and strongly elongated, not curved, with up to five thin spines (Fig. 45F), posterior side with circa 13 sclerotized teeth (Fig. 45G). Single stridulation rib on each male harp (Fig. 45D) and one on each side of female washboard (Fig. 45A). Third podomere of anterior telopods elongated (Fig. 45E). Two locking carinae on the anal shield, anterior carina short, posterior one four times longer than first, straight. Operculum of vulva of special shape, apical margin strongly notched, elongated into two long, sharply-pointed lobes, resembling bovine horns. Lateral lobe slightly larger than mesal one (Fig. 45B).

Similar species: The shape and position of the locking carinae and vulva clearly mark Z. corystoides as a member of the platylabum-group. The special-shaped posterior telopods are quite similar to Z. broelemanni , n. sp., but the fixed finger is more strongly curved. The special-shaped operculum is a unique feature among Sphaerotheriida .

Description: Body length: Males (31 specimens): length up to 28 mm, width of thoracic shield up to 15.9 mm, height of thoracic shield up to 8.5 mm, height of anal shield up to 10.5 mm. Females (4 specimens): length up to 33 mm, width up to 17.0 mm, height up to 9.8 mm, height of anal shield up to 12.4 mm. Females up to 5 mm larger than males.

Habitus: Specimens reach their highest point at posterior body end. Anal shield huge, covered in both sexes anteriorly with dense field of short hairs. Depressions of thoracic shield wide. Tergites smooth, only on posterior margin with few isolated hairs.

Coloration: Head, collum, tergites and anal shield shiny black. Legs and antennae red.

Head: Eyes with more than 70 ocelli.

Epipharynx: With very prominent apical tooth (Fig. 46C). Remaining part similar to those of other species of the genus (Wesener & Sierwald 2005A).

Antennae: Length of antennomeres: 1<2=3>4>5<6 (Fig. 46A), sixth antennomere bearing disc with 17–32 apical cones (Fig. 46B). First antennomere of greatest width, short and cylindrical, with groove, without sensilla basiconica (Fig. 46A). Sclerotized teeth at base of antennomeres 1–3 (Fig. 46A).

Mandible: Seven rows of pectinate lamellae, number of teeth declining from apical to proximal (Fig. 46D). Condylus with one strong developed step near apical margin (Fig. 46D).

Gnathochilarium: Lateral of palpi four sensory cones located together. Depression on posterior side of palpi without sensory cones.

Collum: Whole collum covered with short hair.

Thoracic shield: Concave lateral extension wide and hollowed-out.

Tergites: Smooth and mostly glabrous. Paratergites projecting slightly posteriorly.

Endotergum: Inner section with numerous short spines and long bristles (Fig. 47D). Between marginal ridge and inner area with one row of circular cuticular impressions. Patterns small, in regular distance of each other, distance equal to 2 or 3 times of their diameter (Fig. 47D). Externally two rows of marginal bristles, standing closely to each other. Bristles scaly and short, reaching up 1/2 – 2/3 towards tergite margin (Fig. 47D).

FIGURE 045. Zoosphaerium corystoides n. sp., A, B female paratype, C–G holotype, A: female washboard; B: left second coxa and prefemur with vulva, posterior view; C: last two podomeres of anterior telopod, lateral view; D: right half of anterior telopod, anterior view; E: last three podomeres of anterior telopod, posterior view; F: posterior telopod, anterior view; G: chela of posterior telopod, posterior view. Abbreviations: cav = cavity; cr-t = crenulated teeth; Cx = coxa; EP = external plate of vulva; IH = inner horns; IP = mesal plate of vulva; O = operculum; Pre = prefemur; s-p = sclerotized spot; scl-t = sclerotized teeth; SR = stridulation ribs. Scale bars = 1 mm.

FIGURE 046. Zoosphaerium corystoides n. sp., paratype, SEM, A: antenna, lateral view; B: antenna, apical view on disc; C: epipharynx, apical view; D: right mandible, mesal view. Abbreviations: 3iT = 3 inner teeth; Co = condylus; Endo = endochilarium; eT = external tooth; mp = molar plate; pL = pectinate lamella.

Anal shield: Sexually dimorphic, in females only anteriorly with dense field of short hairs, in males whole surface covered by dense field of minute hairs. Ventral side of anal shield with two black locking carinae, located closely to laterotergites. Anterior carina small, dot-like, posterior carina straight and long, four times longer than first.

Legs: Tarsi of first pair of legs with four or five, second with four to six and third with seven ventral spines. First two leg pairs with only weakly curved claws and without apical spine. Tarsi of legs 4–21 with curved claws, 9–12 ventral spines and one apical spine. Femur 1.9 and tarsi 3.9 times longer than wide.

FIGURE 047. SEM, endoterga of midbody tergites, holotype A: Zoosphaerium pseudoplatylabum n. sp.; B: Z. solitarium n. sp.; C: Z. tsingy n. sp.; D: Z. corystoides n. sp. Abbreviations: ci = cuticular impressions; IA = inner area; mb = marginal bristles; mr = marginal ridge.

Stigmatic plates: First lobe long with well-rounded tip.

Female sexual characters: Subanal plate with washboard consisting of short, but broad and welldeveloped stridulation ribs, with single rib on each half (Fig. 45A). Vulva large, covering more than 2/3 of coxa surface. Operculum long, extending beyond coxa up to middle of prefemur. Apical margin of operculum medially deeply notched, divided into two thin and long lobes with pointed tip, resembling horns of bovine (Fig. 45B). Mesal plate long, extending beyond coxa almost up to 2/3 of operculum's height (Fig. 45B.

Male sexual characters: Anal shield covered with minute hairs.

Anterior telopods (Figs 45C–E): Podomeres 1–3 covered on both sides with isolated long hairs. First podomere width greater than height; harp with one stridulation rib, rib of medium length and well-developed. Second podomere process lobe-like and little curved with rounded edges, reaching up to half of third podomeres height, apically with sclerotized spots, basally with thin spine. Third podomere long, almost as long as first podomere, cavity mesally with numerous sclerotized spots and five thin, sclerotized spines, laterally with circa 11 crenulated, small teeth. One sclerotized spot located closely to tip.

Posterior telopods (Figs 45F, G): Movable finger slender and long, length 4.0 times greater than width, not tapering towards well-rounded tip. Hollowed-out inner margin with five small, sclerotized spines, posterior aspect with circa 13 small, sclerotized teeth. Movable finger slightly longer than fixed finger, latter slender, only tip slightly curved. Margin of fixed finger apically covered with few, minute sclerotized spots. All podomeres covered on both sides with numerous, long isolated hairs, only tips of chela glabrous. Inner horns of syncoxite with pointed, slender tip.

Intraspecific variation: The number of apical cones on antenna varies a lot, even in the same specimen. Too few specimens are known to evaluate the intraspecific variation. The specimens from 1300 m showed no morphological differences to those from the type series, coming from 925 m elevation.