Zoosphaerium platylabum (de Saussure & Zehntner, 1902)

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 : 53

Key to species of the Z. platylabum species-group:

1. Movable finger of posterior telopods very thick, <2 times longer than wide (Fig. 36D). Podomere width strongly decreasing towards tip; apically with minute sclerotized nubs on posterior as well as on anterior side (Fig. 36C). .. 2

- Movable finger slender, at least 3 times longer than wide. Podomere width not decreasing towards tip; apical sclerotized structures only present on posterior side. ................................................................................................. 3

2. Movable finger 1.2 times longer than wide, at inner margin with small membranous lobe. First stigmatic plate greatly enlarged, lobe not triangular or tapering towards tip. Antenna with more than 35 apical cones. ..................... ............................................................................................................... Z. platylabum ( de Saussure & Zehntner, 1902)

- Movable finger 1.6 times longer than wide (Fig. 36D), at inner margin without lobe (Fig. 36C). First stigmatic plate large, lobe triangular and tapering towards well-rounded tip. Antenna with 23–35 apical cones (Fig. 37A). .............. ........................................................................................................................................... Z. pseudoplatylabum , n. sp.

3. Anterior edges of thoracic shield slightly projecting towards head (Fig. 39B). Movable finger shorter fixed finger (Fig. 40F). ...................................................................................................................................... Z. solitarium , n. sp.

- Anterior edges of thoracic shield well-rounded. Movable finger at least slightly longer than fixed finger. .............. 4

4. Operculum of vulva with two well-rounded lobes, lateral lobe twice as wide as inner one (Fig. 42A). Male harp with two stridulation ribs (Fig. 42B). Movable finger 3 times longer than wide (Fig. 47F). ....................... Z. tsingy , n. sp.

- Operculum of vulva with two sharp-edged lobes, both lobes of similar width (Figs 45B; 48C). Male harp with single stridulation rib (Fig. 45D). Movable finger 4 or 5 times longer than wide (Fig. 45F). .............................................. 5

5. Up to 35 mm long. Tergites shiny black, appendages red. Anal shield strongly developed, shaped like a helmet. Operculum of vulva deeply notched, divided into two sharp 'horns' (Fig. 45B). Female washboard on each side with single stridulation rib (Fig. 45A). Fixed finger slightly curved towards movable finger (Fig. 45F). ............................ ........................................................................................................................................................ Z. corystoides , n. sp.

- Up to 55 mm long. Tergites and appendages dirty olive-brownish. Anal shield well-rounded. Operculum of vulva only very shallowly notched, forming two sharp horns (Fig. 48C). Female washboard with four stridulation ribs. Fixed finger running parallel to movable finger (Fig. 48H). ....................................................... Z. broelemanni , n. sp.