NEW SUBFAMILY AND GENUS ACHATINIDAE 



29 



large aperture, the slender arcuate columella, the transverse 

 stripes, the translucence of the shell showing the pattern 

 through the aperture, and the locality indicate that his 

 specimen is Bourguignat's species. 



Bequaert & Clench (1934c) found nine purchased (Her- 

 mann Rolle) specimens from Utengule, Tanzania in the 

 Berlin Museum (ZMB) that were marked as new and given a 

 preempted manuscript name, but were undescribed. 

 Although they felt the new taxon 'might perhaps prove to be 

 a local race' of Callistoplepa nyikaenisis , its more slender, 

 more tapered shape convinced them it should be established 

 as the new species Callistoplepa thielei. The largest specimen 

 previously had been broken, so they selected the second 

 largest specimen as the holotype (Figs. 45, 46). In addition to 

 the holotype, they figured two paratypes. This series of four 

 types (ZMB no. 53177) are in Berlin (Kilias, 1992). Examina- 

 tion of these types in Berlin in 1989, showed evidence that the 

 paratypes had been broken apparently on their return to 

 Berlin because their fragile shells had been stuffed exces- 

 sively with cotton, leaving only the holotype undamaged. The 

 five other original specimens, 3 full grown and 2 juveniles, 

 are labeled paratypes (MCZ no. 98686) in the Harvard collec- 

 tion. Three other broken specimens with the same data are in 

 Frankfurt (SMF); there is no evidence that these were seen 

 by Bequaert & Clench. 



Type locality. Bourguignat (1889) states,' . . . provient 

 des environs de l'Ougerengere, vallee du Kyngani, dans 

 l'Oukani'. Inside the lip of the holotype, in Bourguignat's 

 handwriting, is 'Serpaea pintoi Ougerengere (Oukami). A 

 small label bears the inscription 'M. Requin 1846 30'. 

 According to B. Verdcourt (in litt.), Ukami is a large 

 geographic district that surrounds and includes the Uluguru 

 Mountains in Tanzania. The Kingoni river and the Ngeren- 

 gere settlement and stream, however, place the type locality 

 close to 7° 03' S, 38° 31' E, 125 km west of Dar-es-Salaam (cf 

 Verdcourt, 1966:111). 



Distribution. This is by far the most widespread species in 

 the genus. The 32 recorded localities define a 1800 x 1200 

 km territory 4-20° S, 27-39° E that includes eastern Zaire, 

 eastern and western central Tanzania, nearly all of Malawi, 

 south central Zambia, southern and eastern Zimbabwe, and 

 far west central Mozambique (Fig. 16). The northern outpost 

 of this species was established in Zaire by R. Grauer in 1910, 

 when he found and preserved in alcohol a specimen in 'the 

 primary forest behind bordering hills of the northwest shores 

 of Lake Tanganyika, 1800-2200 m' (trans. ) 4° 30' S, 29° 00' E. 

 It is noteworthy that along the west, there is an almost 

 straight N-S line of demarkation 27-28° E from eastern 

 central Zaire to south central Zambia and southwestern 

 Zimbabwe. Connolly, in his writings (1925, 1939) and on 

 some of his specimen labels, juxtaposes the geographic names 

 Macequece (a district in eastern central Mozambique) and 

 Lourengo Marques (the major port now known as Maputo in 

 southern Mozambique). Specimens may have been shipped 

 from this port, but there is no convincing evidence that this 

 species has ever been collected in Mozambique south of the 

 Macequece district. The remarks of Germain (1935:4) seem 

 to clarify when he explains that Portuguese East Africa is 

 generally divided into two large regions separated by the 

 Zambeze River, 'le Mozambique au Nord, le Lourenzo 

 Marques au Sud'. When adequate population studies can be 



made in this widespread species, valid subspecies may 

 emerge. 



Remarks. This apomorphic species is most closely related to 

 B. marteli. Both Achatina craveni E.A. Smith, 1881 and B. 

 pintoi are highly variable and are often confused in collec- 

 tions, particularly where the field data are the same or the 

 individuals are small. Despite rather considerable overlap in 

 the extremes of the conchological characters of these two 

 species, the shell of A. craveni can be differentiated on the 

 basis of the following: nepionic whorls smooth; last whorl 

 equals only 70-75% of shell length (vs 80-90%); one to two 

 more whorls for the same length; apex more acute; columella 

 much shorter, broader, straighter and more squarely trun- 

 cated; finer and deeper granulate-cancellate sculpture; shell 

 usually much less fragile. 



The wide distribution and the independently great variabil- 

 ity in shell characters, even within a single population, are 

 responsible for the long and confused synonymy of this 

 species. The soft anatomies of antipodal specimens, and 

 many between, support the conclusion that only one species 

 is involved. 



Ecological notations with specimen data (HM, NG) indi- 

 cate that active specimens were found in Malawi lowland 

 evergreen forests, along the banks of earth roads, crawling on 

 leaf litter, and on the underside of banana leaves in the rain. 

 Specimens from Mbeya, Tanzania were found in luxuriant 

 herbaceous vegetation (LNK). The director of the Imperial 

 Institute of Entomology earlier reported that in the Nkota- 

 Kota district of Malawi there was a 'very serious outbreak in 

 November 1937', implying that this species has the potential 

 under certain conditions of becoming an agricultural pest. In 

 Zambia this snail is know as 'chuzuya'. 



The fine series of specimens in BMNH convincingly dem- 

 onstrates the wide range of variability in the shells of this 

 species (Figs. 41-51). 



Bequaertina fraterculus (Dupuis & Putzeys, 1900) 

 Figs. 52, 53 



Ganomidos fraterculus 



Dupuis & Putzeys, 1900:xiii, text fig. 18. 

 Callistoplepa fraterculus 



Pilsbry, 1905:129, pi. 47, fig. 23 (ex Dupuis & Putzeys); 



Germain, 1909:90; Pilsbry, 1919:80; Bequaert & Clench, 



1934c: 114. 



Shell. Shell ovate-turrite, extremely thin, translucent. 

 Whorls 6-6'/4. The second and third whorls are comparatively 

 large, long and nearly straight-sided, producing characteristi- 

 cally a collared blunt mammillate apex. The fourth and 

 subsequent whorls are convex and expanded proportionately. 

 Sutures moderately deep. Last whorl large, but not inordi- 

 nately so, 78% of shell length; range for 6-6'A whorls, 

 77-80% (n = 10). Aperture oval, pale milky within. Col- 

 umella brown, long, slender, nearly straight, obliquely trun- 

 cated. Outer lip thin, evenly arcuate; receding at base in 

 profile. Parietal callus diaphanous. 



Highly irregular castaneous streak and spot brush marks, 

 some of which are closely highlighted with buff adaperturally, 

 are characteristically found on the last whorl; however, these 

 may be reduced to a few obscure dull buff spots more or less 

 limited to the peripheral carina. The earliest signs of this 

 diagnostic colour pattern are seen in the third whorl. The 

 ground colour intergrades from pale horn colour of the 



