Pleonoporus robustus Attems, 1938

Enghoff, Henrik & Akkari, Nesrine, 2022, A new species of the hitherto monospecific genus Pleonoporus Attems, 1938 (Diplopoda, Spirostreptida, Odontopygidae), ZooKeys 1117, pp. 189-202 : 189

Pleonoporus robustus Attems, 1938

Figs 5 , 6 , 7

Diagnosis.

Very similar to Pleonoporus tanzanicus sp. nov., from which it differs by the absence of the lateral coxal spine (LCS) on the gonopods.

Material examined.

Syntypes: 6 ♂♂ (four of them broken in halves), 1♀ (NHMW MY 2666), one gonopod block (NHMW MY 9061), gonopods separated into left and right gonopod (NHMW MY 9062); 1 micro-preparation with fragment of a body ring; "Demokrat Republik Congo /Provinz Katanga, Elisabethville [Lubumbashi]/led. Denis A. 1935/don. Kong Mus./Attems 1937."

Comments.

Attems (1938) mentioned a small projection on the ventral side of the anal valves "ein winziges Höckerchen” in his original description of the species. This structure was visible only in two of the male syntypes (Fig. 5E , arrow), whereas the rest of the specimens showed a regular ventral margin or just a slightly angular one. We dissected one of the males having anal valves with a regular ventral margin, and it showed gonopods identical to those described by Attems.

It was not possible to find the specimen from which Attems dissected and extracted the gonopods. However, the gonopod illustrations ( Attems 1938: figs 86-89) perfectly match our illustrations (Figs 6 - 7 ) of the loose gonopods found in the jar, which we put in a separate vial (NHMW MY 9062). These may very well be the gonopods illustrated by Attems in the original description of the species.

Figures

Figure 5. Pleonoporus robustus Attems, 1938. Syntype ♂ (NHMW MY 2666) A male, in toto lateral view B head and anteriormost rings, lateral view C close-up of gonopod in situ, lateral view D posterior-most rings and telson, lateral view E close-up of the telson, arrow indicating ventral projections. Scale bars: 5 mm (A); 1 mm (B-D).

Figure 6. Pleonoporus robustus Attems, 1938. Syntypes ♂ gonopods A gonopod block (NHMW MY 9061), anterior view B left gonopod, posterior view (NHMW MY 9062). Abbreviations: CU = cucullus; hu = lateral hump; MP = metaplica; msp = metaplical spine; mts = metaplical transverse spine; PP = proplica; Scale bars: 1 mm.

Figure 7. Pleonoporus robustus Attems, 1938. Syntype ♂ gonopods (NHMW MY 9062) A right gonopod, anterior view B antero-mesal view. Abbreviations: al = anterior lobe of telomere, CU = cucullus; hu = lateral hump; MF = metaplical flange, MP = metaplica; msp = metaplical spine; mts = metaplical transverse spine; PP = proplica; pl = posterior lobe of telomere, SLM = solenomere; TM = telomere; TT = torsotope. Scale bars: 1 mm.