Bicoxidens grandis, Lawrence, 1965

Mwabvu, Tarombera, Hamer, Michelle L. & Slotow, Robert H., 2007, A taxonomic review of the southern African millipede genus, Bicoxidens Attems, 1928 (Diplopoda: Spirostreptida: Spirostreptidae), with the description of three new species and a tentative phylogeny, Zootaxa 1452, pp. 1-23 : 10-11

B. grandis Lawrence, 1965

Fig. 5

Bicoxidens grandis Lawrence, 1965 ; Krabbe, 1982; Hamer, 1998; Mwabvu, 2000, 2005 Rhodesiostreptus matabele Schubart, 1966 syn. n.

Bicoxidens matabele Krabbe, 1982 ; Hamer, 1998; Mwabvu, 2000

Type material B. grandis (examined): Holotype: ZIMBABWE: 1 ɗ, 15 km West of Birchenough Bridge [19°50'S, 32°30'E], 20.ii.1962, D. G. Broadley ( NMSA 8884)

Type material B. matabele (examined): Holotype: ZIMBABWE: 1 ɗ, WN West Nicholson, 6.v.1951 ( MZLU /L951/3730)

Additional material examined: ZIMBABWE: 1 ɗ, Silobela [19º20' S, 29º35'E], xi.1997, T. Mwabvu (NMZ uncatalogued); 1 ɗ 2Ψ, Birchenough Bridge [19°55'S, 32°35'E], 1998, T. Mwabvu ( NMSA 20528); 1 ɗ 3Ψ, Zvomukonde [20º50'S, 30º30'E], xii.1998, T. Mwabvu (NMZ uncatalogued); 2 ɗ 4Ψ, Silobela [19º20' S, 29º30'E], xii.1998, T. Mwabvu ( NMSA 20546).

Diagnosis: Apical telocoxite with a horizontal apically acute lateral process and a curved median process that overlaps with median process from opposite gonopod ( Figs. 5 a, 5b). Aborally, an apical ear-shaped lobe present on lateral leaf at same level as axe-shaped median process.

Description:

Size: Body length 135 mm; minimum and maximum body width 7–8 mm and 8–11 mm; antenna length 7–9 mm

Number of body rings: 52–62.

Colour: Body black; antennae and legs brown.

Collum: With three complete folds ( Fig. 5 d).

Pre-femoral process of 1st pair of male legs: Proximal halves parallel, almost touching; rounded distally, with apical nipples deflected to face the other ( Fig. 5 c).

Sigilla on body ring: Three rows, becoming one ventrally.

Gonopod: 6–7 mm long. Orally, apical telocoxite with a lateral and median process ( Fig. 5 a). Median process crescent-shaped and overlapping the opposite process. Lateral process horizontal, long and apically acute. Distally, median leaf with median axe-shaped process not touching the opposite one ( Fig.5 a).Femoral lobe typically long, ( Fig. 5 a).

Aborally, a small almost ear- shaped transverse projection is present on the lateral leaf ( Fig. 5b ) at same level as the axe-shaped process ( Fig. 5b ).

Distribution: Current records are from southern Zimbabwe ( Fig.10)

Remarks: The gonopod of Rhodesiostreptus matabele Schubart, 1966 is identical to that of B. grandis , and the taxa also have overlapping distributions. Additionally, they both have an ear-shaped projection on the lateral leaf behind the median leaf apex, as well as identical telocoxites and median leaves and a telopodite with a much longer femoral lobe unlike the other species of Bicoxidens . B. matabele is therefore a junior synonym of B. grandis .

Although grandis is larger than flavicollis , their gonopods are similar in that they have overlapping, flattened median processes on the distal telocoxites and axe-shaped processes on the median leaf unlike the other species. The two species are, however, quite distinct; flavicollis does not have a lateral process on the apical telocoxite or an aboral ear-shaped projection on the lateral leaf. Unlike flavicollis , the paracoxite of grandis is not tightly attached to the lateral leaf as in friendi and gokwensis . B. grandis has only been recorded in hot and dry areas.

Abbreviations: asp, axe-shaped process; at, apical telocoxite; cf, collum fold; fl, femoral lobe; llp, lateral leaf projection; ll, lateral leaf; lp, lateral process; mp, median process; pc, paracoxite; pfl, prefemoral lobe; st, sternite; tp, telopodite

Figures

FIGURE 5. B. grandis (NMSA 8884). a, oral view of gonopods; b, aboral view of gonopods; c, oral view of prefemoral lobe of first pair of male legs; d, lateral view of collum.