Cacuminostreptus triangulatus, Mwabvu, Tarombera, Hamer, Michelle, Slotow, Rob & Barraclough, David, 2010

Mwabvu, Tarombera, Hamer, Michelle, Slotow, Rob & Barraclough, David, 2010, A revision of the taxonomy and distribution of Archispirostreptus Silvestri 1895 (Diplopoda, Spirostreptida, Spirostreptidae), and description of a new spirostreptid genus with three new species, Zootaxa 2567, pp. 1-49 : 35-40

Cacuminostreptus triangulatus sp. n. Mwabvu

Fig. 13

Type material: Holotype: ZIMBABWE: 1 3, Sahwe River, Mavuradona [1631A3], 8.xi.1989, D. G. Broadley (NMZ/D568)

Etymology: Refers to the triangular shape of the apical metaplical process.

Diagnosis: Apical metaplical processes triangular, touching proximally and separate distally forming Vshape ( Fig. 13a ).

Description: Size: Body length 140 mm; maximum body width 11 mm.

Number of body rings: 61.

Colour: Body dark brown; legs and antennae light brown.

Collum: Anterior produced into narrow lobe, with 3 complete striae ( Fig. 13d ).

Pre-femoral process of 1st pair of male legs: Proximally oval with long laterally deflected mesial extension ( Fig. 13c ).

Gonopod: ( Figs 13a, 13b ) Apex of sternum reaching level of paracoxite apex; paracoxite fused tightly to metaplica, apex flat.

Telocoxites touching and parallel up to level of apical metaplical process ( Figs 13a, 13b ).

Proplicae broadly rounded apically; central groove of proplica flanked by gently raised edges. Medial lobe of distal proplica short and rounded apically.

Opposite metaplicae separate at level of lateral metaplical process. Medial ridge of metaplicae extend from lateral metaplical process to apex of apical metaplical process.

Lateral metaplical process deflected anteriad, and extending beyond lateral margins of paracoxite; lateral metaplical process narrow proximally, widens and tapering distally. Proximad lobe produced from wider part of lateral metaplical process, lobe extending towards telopodite ( Fig. 13a ).

Lateral metaplical process and apical metaplical process at acute angle ( Fig. 13a ).

Apical metaplical process triangular, slightly deflected laterally and wider apart distally; apical metaplical process shaped like an inverted triangle ( Fig. 13a ). Medial edges of opposite apical metaplical processes form a V-shape distally.

Distribution: Known from a single locality at the Sahwe River in Mavuradonha Wilderness Area, in western Zimbabwe

Remarks: The triangular shape of the apical metaplical process of the gonopod distinguishes C. triangulatus from congeners. However, the shapes of the lateral metaplical process and antetorsal process do not show significant difference from those of C. conatus , C. mazowensis and C. vumbaensis . The medial edges of the opposite coxites of the gonopod of C. triangulatus seem to be fused up to the level of the lateral metaplical process as in the gonopods of C. mazowensis .

Figures

FIGURE 13 a, b. Cacuminostreptus triangulatus (NMZ / D 568). a, oral view of gonopods; b, aboral view of gonopods.