24 



and irregular. Last whorl large, 80% of shell length; range for 

 5-7V2 whorls, 76-84% (n = 52). Aperture oval, faint milky 

 wash within. Columella concolorous, slender, moderately 

 long straight or slightly arcuate and rectangularly to very 

 obliquely truncate. Outer lip extremely thin, evenly arcuate, 

 receding at base in profile. Parietal callus scarcely detectable. 



The first two to three whorls are light horn colour. Pale, 

 obscure, castaneous streaks begin to appear in the third or 

 fourth whorl; these characteristically are broader at the 

 suture below, becoming increasingly darker, larger and more 

 irregular on the last whorl. These streaks may be variously 

 vertical, diagonal, angulate, flammulate, interrupted, or 

 reduced to spots and blotches. Ground colour is dull buff to 

 dull olivaceous-fulvous. Of 56 specimens checked precisely 

 for colour, 63% have a definite pattern, 7% are nearly 

 unicolorous, and 30% are unicolorous. There was no correla- 

 tion between colour pattern and locality. 



The first whorl is essentially without sculpture. Minute, 

 faintly engraved crescentic granulations usually appear early 

 in the second whorl; these are formed by nearly equidistant 

 spiral lines and irregular, scalloped transverse lines. The 

 latter become straighter and compressed in the third whorl, 

 producing narrow elongate granulations and irregularly 

 appearing prosocline growth wrinkles that are crenulate at 

 the suture. The sculpture becomes more disperse in the 

 fourth and fifth whorls, producing a dominant, fairly uni- 

 form, subquadrate, often welt-like, cancellate-granulate 

 sculpture, which usually fades quickly at the periphery. In the 

 sixth to seventh whorls, this sculpture becomes more and 

 more subdued and diffuse until the increasingly prominent, 

 yet modest, growth wrinkles dominate both above and below 

 the periphery. In the largest specimens of seven whorls the 

 cancellate-granulate sculpture may feebly or strongly return 

 both above and below the periphery. The dull, extremely 

 thin, tenaceous outer periostracal layer wears off in very 

 limited areas, highlighting the sculpture with the exposed 

 glossy inner periostracal layer. 



Soft anatomy. No known alcohol preserved specimens. 



Type material. As nearly as can be determined, Putzeys 

 had 14 syntypes of his Ganomidos pellucidus, for which he 

 gave a range of shell dimensions (1898). The specimens were 

 collected by P. Dupuis. Putzeys retained a select series of 7 

 syntypes in his own collection (MRAC no. 5132-5138). He 

 did not designate types, but selected the largest specimen 

 (no. 5132) for an abaperatural view and a small specimen with 

 slender flames (no. 5133) for an aperatural view in his line 

 drawing illustrations. Regrettably, the larger specimen had 

 been rather badly damaged and mended in nature, and the 

 smaller specimen was excessively small. The second largest 

 syntype in his series (no. 5136) is a unicolorous specimen that 

 is representative of only about a quarter of the known 

 specimens (Figs. 33, 34). Hence, the flamed, third largest 

 syntype in his series (no. 5 135) is here selected the lectotype 

 (Figs. 31, 32; Table 6), with the other syntypes becoming 

 paralectotypes (BMNH lno. 1904.5. 18.68, IRSN 5, MRAC 6, 

 NHMW 1). 



On the basis of two specimens collected by Edouard Foa 

 during his 1897-98 expedition to the Lake District of Africa, 

 Germain described (1905) and figured (1908) the junior 

 subjective synonym Serpaea foai from 'Tanganika est', later 

 corrected to 'les bords du Lac Tanganyika'. Bequaert (1950) 

 placed Serpaea in the synonymy of Achatina, but apparently 



A.R. MEAD 

 Table 6 B. pellucida - Representative shells measurements. 







Greatest Aperture 



Last 



/o 





Whorls 



Length 



Width 



Length Width whorl LW/L % W/L 



7 



60.4 



31.4 



32.7 



19.5 



45.9 



76 



52 Mweru 

 (BMNH) 



7Vz 



58.6 



32.8 



36.0 



16.6 



46.0 



79 



56 Kamina 

 (MRAC) 

 581.196 



7 



54.5 



29.0 



30.5 



17.0 



42.5 



78 



53 Mweru 

 (BMNH) 

 1907.11. 

 11.5 



7 



53.3 



30.2 



31.2 



17.8 



42.3 



79 



57 Mpala 

 (IRSN) 



6V2 



48.0 



28.0 



29.7 



15.8 



38.0 



79 



58 Piani 

 Kapuri 

 (MRAC) 

 5132 PLec 

 G.p. 



6V2 



46.9 



29.6 



29.4 



16.5 



37.5 



80 



63 Tanganyika 

 (MNHN) 

 Lect 5. 

 foai * 



6V4 



45.8 



28.0 



28.0 



16.7 



37.0 



82 



61 Piani 

 Kapuri 

 (IRSN) 

 PLec G.p. 



6V2 



45.0 



28.2 



26.8 



15.5 



35.5 



79 



63 Piani 

 Kapuri 

 (MRAC) 

 5136 PLec 

 G.p.* 



6V4 



43.2 



24.6 



25.5 



14.1 



33.9 



78 



57 Piani 

 Kapuri 

 (MRAC) 

 5135 Lect 

 G.p.* 



6V< 



40.4 



22.6 



23.0 



13.6 



31.7 



78 



56 Piani 

 Kapuri 

 (MRAC) 

 5133 PLec 

 G.p. 



6 



39.0 



23.3 



24.4 



14.1 



32.0 



82 



60 Tanganyika 

 (MNHN) 

 PLec S. 

 foai 



5% 



35.5 



20.0 



20.9 



12.0 



28.4 



80 



56 PLec G.p. 

 (BMNH) 

 1904.5. 

 18.68 



Total specimens examined: 62. Sources: BMNH, IRSN. MCZ, MNHN, 

 MRAC, NMW, USNM, ZMB. 



overlooked Germain's species. Only Verdcourt (1966) has 

 acknowledged the existence of this species, and then only as 

 an East African species unknown to him. A study of the two 

 syntypes in Paris (MNHN) confirmed the fact that they are 

 indeed Putzeys' species. His larger, sharply photographed 

 'seul adulte' specimen (Figs. 35, 36) is here selected as the 

 lectotype of Germain's Serpaea foai (Table 6). 



Deshayes (1824-37, 1864) described and illustrated a small 

 fossil snail Agathina pellucida (= Achatina pellucida) from the 

 Paris basin. Lamarck (1838:313) also refers to this species. 

 This very acuminate, slender specimen is possibly a subulinid. 

 It does not enter into homonymy with Putzeys' G. pellucidus 

 because the latter was never included in the genus Achatina. 



