32 



A.R. MEAD 



shown here, had a bifurcate insertion; a multiple insertion is 

 not rare in the achatinids. At the origin of the PR, the muscle 

 fibrils enshroud smoothly and completely the apical P and the 

 robust basal vas deferens (BVD), greatly obscuring the 

 relationships in the basal male conduit (Fig. 21). Contributing 

 to this, the PS is free from the P only in the approximate 

 upper half of the left side. On the right side, fibrils from the 

 PR extend basally to form a dense webbing that seems to 

 invade the substance of the outer wall of the P and the inner 

 wall of the PS. Below the PS, this infusion of tissues, along 

 with the EM, obscurely defines the wall of the penial atrium. 

 This atrium connects the lumina of the P and GA (Fig. 22). 

 The lumen of the P is thickly carpeted with vermiculate 

 rugae, which become slender and elongate near the GA, 

 resembling the plicae of the basal V. No verge or pilaster is 

 present. Eccentrically in the apex of the P, a small aperture 

 leads to the narrow lumen of the extremely thick-walled BVD 

 and AVD. These two structures provide the physical support 

 for the extroverted, highly expansile P. Since they have 

 supportive and ejaculatory functions, they may explain the 

 extreme development of the VR. Approximately 8-10 mm 

 basal to the junction of the AVD and FO, the lumen of the 

 AVD enlarges considerably and forms an elongate, thin- 

 walled chamber, which conceivably functions as a secondary 

 seminal vesicle (SSV). Apically this chamber becomes saccu- 

 lar with thin elongate rugae. 



A single specimen (610.343) was gravid. Six large, fully 

 formed eggs, 9.5 x 6.5 mm, were in the apical (oviductal), 

 cream coloured portion of the spermoviduct; no eggs were in 

 the contrastingly light brown uterine basal portion. This 

 specimen and the five others in the same lot had robust, 

 mature coloured, fully formed reproductive tracts. The field 

 data thus indicate that in the Kivu, breeding takes place in 

 October. 



Kidney is large, typical of the subfamily, broad anteriorly 

 and truncated posteriorly. Five ovotestis acini are embedded 

 in the columellar surface of the right (apical) lobe of the 

 digestive gland. The inconspicuous anterior aorta is on the 

 left posterior surface of the lung, where it penetrates the 

 diaphragm. The hermaphroditic duct, similar to that of B. 

 pintoi (Fig. 19), is trimerous with an abruptly enlarged 

 saccular central portion, 5.3 x 2.4 mm. 



The following anatomical characters distinguish this species 

 from B. pintoi: basal genital fascia gross, forming a VR with a 

 massive system of muscle bands; AVD, BVD and FO are all 

 about the same width; P is strikingly short and stubby, 

 normally retained entirely or nearly entirely within the PS; 

 BVD wide, about as long as wide. 



Type material. Thiele (1911) described this species from a 

 single mature specimen (ZMB no. 101937) in the Schubotz 

 collection and two small juvenile specimens from the Grauer 

 collection. The mature specimen is nearly full grown but only 

 moderately large (Figs. 54, 55; Table 10). Thiele's fine line 

 illustration shows it slightly larger than natural size in aper- 

 tural view only. This specimen, whose soft parts are in 

 alcohol, I labelled as the lectotype of Thiele's Achatina 

 graueri when I examined it in East Berlin (ZMB) in August 

 1989. At that time, the single available very dark coloured 

 juvenile specimen (Table 10) therefore was labelled paralec- 

 totype. Since then a second small paralectotype has been 

 found there and so labelled by Kilias (1992). 



Germain (1936), without any apparent knowledge of 

 Thiele's species, described and figured the junior subjective 



synonym Callistoplepa babaulti from two specimens collected 

 by Babault in Kitembo, Kivu, comparing it only with C. 

 marteli. The two Paris syntypes (MNHN) are large, typical 

 specimens of Bequaertina graueri (Table 10). The larger, 

 finer specimen is here selected as the lectotype of Germain's 

 C. babaulti (Figs. 56, 57). 



Type locality. Idjwi Island (= Kwidschwi, Kwidjwi, 

 Idjewi), Lake Kivu, Zaire 2° 09' S, 29° 04' E. 



Distribution. This species occupies a 450 km long, narrow, 

 north-south corridor in the upper Rift Valley of Zaire 

 between Beni and Uvira (Fig. 16). So far, it has been found 

 only as far west as Kitembo and projects slightly east of Zaire 

 into Lobengera Mission, Rwanda and into Ibanda, Uganda. 

 Eventually, it will also be found in Burundi. 



Remarks. This is the largest and most distinctive species in 

 the genus. It is most closely related to Bequaertina fratercu- 

 lus. Because of its size and colour, and because in some 

 localities it is sympatric with Achatina stuhlmanni von Mar- 

 tens, 1892, it has been confused with that species. However, 

 since A. stuhlmanni has a shorter, broader spire, a more 

 obtuse apex, and a distinctive spirally fine-combed wavy 

 sculpture (Bequaert & Clench, 1934a:3), it can readily be 



Table 10 B. graurei - Representative shells measurements. 



Greatest Aperture Last % 

 Whorls Length Width Length Width whorl LW/L % W/L 



7 93.2 



45.7 



52.3 



26.6 



71.8 



77 



49 



Katana 



(MRAC) 

 610.304 



6'/4 89.7 



47.0 



55.5 



28.4 



72.6 



81 



52 Tshibinda 

















(MRAC) 



5115 



7 89.3 



43.6 



50.7 



25.5 



70.0 



78 



49 



Katana 



(MRAC) 



610.302 



6'/4 78.4 



42.5 



46.8 



24.3 



62.5 



80 



54 



Kitembo 

 (MNHN) 

 Lect C. 

 babaulti* 



6 77.0 



38.6 



45.9 



23.5 



63.0 



82 



50 



Uvira 



(MRAC) 



607.170 



6>/ 4 71.8 



41.4 



41.9 



23.4 



56.1 



78 



58 



Kitembo 

 (MNHN) 

 PLec C. 

 babaulti 



6 62.0 



36.5 



37.8 



20.6 



49.1 



79 



59 



Idjwi 

 (ZMB) 

 101935 

 Lect A. 



5% 49.8 



29.1 



31.8 



16.4 



40.0 



80 



58 



grauer?* 

 Idjwi 



6 49.2 



22.8 



31.0 



14.5 



39.5 



80 



46 



(MCZ) 

 Beni 

 (MRAC) 

 5119 



5V4 42.0 



25.7 



27.0 



14.0 



33.0 



78 



61 



Idjwi 

 (ZMB) 

 101936 

 PLec A 



graueri 



Total specimens 



examined: 



54. Sources: IRSN 



I,MCZ 



, MNHN, MRAC, 



NMW, RMNH, 



SMNH, UMMZ, ZMB. 











