Archispirostreptus tumuliporus (Karsch 1881)

Fig. 10

Spirostreptus tumuliporus Karsch 1881, p. 51–52.

Graphidostreptus tumuliporus: Attems 1914

Archispirostreptus tumuliporus: Schubart 1951; Hoffman 1965; Krabbe & Enghoff 1978; Krabbe 1982; Mwabvu 2005

Type material: Holotype: SUDAN: 1 3, Scriba Ghattas, Djur (ZMB 645)

Additional material examined: CHAD: 2 3, Tikem Station IRCT [9 0 45'N, 15 0 00'E], xii.1958, Galichet (MNHN 1B 220). SENEGAL: 1 3, 1 Ƥ, Sine Saloum [13 0 55'N, 15 0 37'W], 4.ix.1970, M. Mühlenberg & R. Streng (MNHN 1B 223). MALAWI: 1 3, (MNHN 1B 251); BENIN: 1 3, Dassa Zoumé [7 0 47'N, 2 0 08'E], 23.xi.1970, Ch. Gasc (MNHN 1B 222). UGANDA: 2 3, 1903, Bourg de Bozas (MNHN 1B 224). MALI: 1 3, 1 Ƥ, Toukoto (150 km E. de la Falémé), [14 0 35'N, 12 0 03'E], vii.1903, Kermorgant (MNHN 1B 225). CAMEROON: 1 3, Batouri [4 0 27'N, 14 0 24'E], 14.i.1993, Jean Dejax, (MNHN 1B 289). ZIMBABWE: 1 3, Muzarabani [16 0 23'S, 31 0 00'E], 1.xii.1998, T. Mwabvu (NMSA 20480); 1 3, Mapembe Mountains, Marange [18 0 57'S, 32 0 27'E], 13.xii.2007, T. Mwabvu (NMSA 21941); 1 3, Chipfatsura School, Marange [18 0 57'S, 32 0 27'E], 20.xii.2005, T. Mwabvu (NMSA 21943).

Diagnosis: Apical metaplical process wide and parallel proximally; distal half of apical metaplical process narrow, becoming acute (Figs 10a, 10b).

Description: Size: Body length 147–200 mm; maximum body width 12.5– 16 mm.

Number of body rings: 59–67.

Colour: Body dark brown or black; legs and antennae brown.

Collum: Laterally square or with a small anterior lobe, with 3–4 complete striae and 2–6 incomplete striae (Fig. 10d).

Pre-femoral process of 1st pair of male legs: Basally round, medial nipple deflected laterally (Fig. 10c).

Gonopod: (Figs 10a, 10b) Sternum rounded apically; paracoxite narrowly rounded and fused tightly to metaplica.

Apical proplica rounded, overlapping lateral metaplical process proximally; medial lobe of apical proplica long and tapering.

Lateral metaplical process wide proximally, tapering distally; lateral metaplical process almost at right angle to apical metaplical process (Fig. 10a).

Apical metaplical process parallel proximally, distal halves wider apart and acute apically.

Distribution: Democratic Republic of Congo, Ghana, Sierra Leone (Krabbe 1982), Chad, Cameroon, Benin, Sudan, Mali, Uganda, Malawi and recently from northern and eastern Zimbabwe.

Remarks: There are significant variations in the form of the gonopods of material identified as A. tumuliporus from different parts of Africa. Some of the gonopods are morphologically distinct from the holotype in the shape of the apical and lateral metaplical processes. We have found in the collections some specimens of A. lugubris from Senegal which had been incorrectly identified as A. tumuliporus (see remarks on A. lugubris).

Gonopod variations in A. tumuliporus relate to the shape, size and orientation of the lateral and apical metaplical processes. The lateral metaplical processes of specimens from Cameroon are spined distally, specimens from Senegal have a slanting lateral metaplical process, which is at an obtuse angle with the apical metaplical process, and the paracoxites differ in shape and angle at which they are fused to the metaplicae compared with specimens from other localities. The gonopods of specimens from Chad have narrow fingerlike apical metaplical processes; distally the apical metaplical processes are similar to those of A. smithii, A. dodsoni and A. lugubris . Based on this evidence, we concluded that A. tumuliporus is a species complex and that several specimens of Archispirostreptus may have been incorrectly identified or assigned to A. tumuliporus because of the broad specific limits that were used.

One subspecies A. t. sudanicus (Brölemann 1905) (synonymized by Attems 1914, p. 159, fig. 164) from Senegal is recognized here as distinct, based on gonopod shape. The gonopod of the subspecies has a relatively narrow apical metaplical process, which is at an acute angle with a slanting lateral metaplical process. Another geographically distinct form from Chad, which has a very narrow and finger-like apical metaplical process, has been identified.