Brevitibius polyptychus (Kraus, 1958) comb. n.

Fig. 9

Bicoxidens ? polyptychus Kraus, 1958

Bicoxidens polyptychus: Krabbe, 1982; Mwabvu, 2000

Type material (examined): Holotype: DEMOCRATIC REPUBLIC OF CONGO: 1 ɗ, Parc Natinal. de L’Upemba, Katanga Province [8º30'S, 26º20'E], 2.iv.1948, G.F. de Witte (HT018.229); Paratype: 3 ɗ, Parc National. de L’Upemba, Katanga Province [8º30'S, 26º20'E], 2.iv.1948, G.F. de Witte (018.130)

Diagnosis: Apical telocoxite with a long diagonal lateral process and a short median process (Figs. 9 a, 9b). Post knee telopodite with torsion and a femoral spine (Fig. 9 c).

Description:

Size: Body length 155–168 mm; minimum and maximum body width 8–10 mm and 10–12 mm; antenna length 8–10 mm.

Number of body rings: 70–72.

Colour: Body, legs and antennae brown.

Collum: With anterior lobe, with 7–9 complete folds (Fig. 9 e).

Pre-femoral process of 1st pair of male legs: Bean-shaped (Fig. 9 d).

Sigilla on body ring: One row.

Gonopod: 8–9 mm long. Orally, apical telocoxite with a long diagonal lateral and a short median process (Fig. 9 a). Aborally, lateral leaf without lobes or processes. Paracoxite arrow-head shaped (Fig. 9 a); sternite reduced. Telopodite with femoral torsion and a black femoral spine distal to it (Fig. 9 c).

Distribution: Katanga Province, Democratic Republic of Congo

Remarks: Unlike Bicoxidens species, this species is large-bodied, the anal valve has one furrow on each side and the collum has an anterior lobe with seven folds. The telopodite is not L-shaped but has torsion; the paracoxite is arrowhead-shaped (not rounded as in Bicoxidens species).

It appears to be closely related to central African species most of which were previously assigned to Spirostreptus in Krabbe (1982). A revision of these taxa needs to be undertaken in order to clarify the position of polyptychus in Spirostreptida .

However, we have tentatively assigned it to Brevitibius Attems, 1950, based on the form of the telopodite. The femoral process is distal to the knee after which there is an abrupt narrowing and twisting of the telopodite around the femoral region, this is consistent with Brevitibius .