B. M. Landau & L. T. Groves 
Novapex 12(1-2): 1-38, 10 mars 2011 
Discussion. Trôna ingrami n. sp. has a rather variable 
shell shape. The larger specimens tend to be more 
rotund and broad (Figs 58-64), whereas the smaller 
specimens hâve a more elongated aspect and a less 
sinuous aperture, but intermediate specimens also 
occur (see Text-figure 4). The single living 
représentative of the genus Trôna stercoraria 
(Linnaeus, 1758) distributed today along the coast of 
tropical West Africa also has a variable shell shape 
(Lorenz & Hubert, 2000; pl. 11 ). Dolin ( 1991 ) hints at 
sexual dimorphism in the species without elaborating, 
however, in Cypraeidae as well as in Ovulidae male 
shells tend to be smaller than females. 
height/length Trôna ingrami 
♦ length/width 
■ length/height 
-Linear (length/height) 
Linear (length/width) 
30 35 40 45 50 55 60 65 
length 
Text-figure 4. Height/ Length; Trôna ingrami n. sp. 
Dolin (1991) describes a light-weight shell with 
uncallused margins, whereas the Cantaure shells are 
very solid with a weakly developed marginal callus. 
His description and figure clearly show the labral teeth 
to be restricted to the inside of the aperture, whereas 
the teeth in T. ingrami extend a short distance over the 
basal plane onto the ventrum where they become 
somewhat coarser. On the labral side the teeth 
abapically are described as short, whereas in T. 
ingrami the outer iip is bevelled inwards with the teeth 
extending across the bevelled inner portion. The 
fossula in T. ingrami has few elongated denticles 
which tend to be continuous and rarely tubercles as 
compared to the specimens of T. calhounensis figured 
by Dolin (1991) (fig. 22a) which has the fossula 
crowded with interrupted ridges and elongated 
tubercles. 
Etymology. Named for William Marcus Ingram in 
récognition of his pioneering work on Caribbean 
Neogene cypraeids. 
Geological and geographical distribution. 
Lower Miocene: Cantaure Formation, Venezuela. 
Trôna trinitatensis (Mansfield, 1925) 
Text-figure 5; Figs 71-77 
1925 Cypraea trinitatensis Mansfield, p. 49, pl. 8, 
fig. 10. 
1939 Trôna (Macrocypraea) trinitatensis 
Mansfield, 1925 - Schilder (partim?), p. 30, fig. 32. 
1947 Cypraea fossula Ingram, p. 4 (128), pl. 1 (8), 
fig. 3. 
1971 Macrocypraea cervinetta fossula Ingram, 
1947 - Schilder & Schilder, p. 33. 
1971 Macrocypraea trinitatensis Mansfield, 1925 
- Schilder & Schilder (partim?), p. 164. 
71971 Macrocypraea aff. zébra (Linné) - Jung, p. 
181, pl. 8, figs 1-3. 
1993 Macrocypraea trinitatensis (Mansfield, 1925) 
- Lorenz & Herbert, pl. 121, fig. 3. 
2000 Macrocypraea trinitatensis (Mansfield, 1925) 
- Lorenz & Herbert, pl. 121, fig. 3. 
2004 Luria (Tessellata) fossula (Ingram, 1947) - 
Dolin & Lozouet, p. 20. 
Material. 1 specimen NMB H18403, NMB coll. (Figs 
71-73); 1 specimen NHMW 2010/0036/0011, NHMW 
coll. (ex. BL coll.) (Figs 74-77). Holotype of C. 
fossula ; UCMP 35536. 
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