. Bulletin of the British Museum (Natural History). . Further occurrences. Late Caenozoic, Pebasian; Pebas (Boettger 1878), Iquitos (de Greve 1938). No other records. Diagnosis. Liris with low, well-rounded, sometimes obsoles- cent, axial folds; spiral sculpture mainly of very weak spiral threads; spire angle between 15° and 27°. DESCRIPTION. The rather high, naticoid, apex is smooth and consists of 2—2V2 whorls. Although rare individuals, including one of the paralectotypes of L. laqueata Conrad, lack axial folding, in most shells axial folding appears on the third whorl. The folds
. Bulletin of the British Museum (Natural History). . Further occurrences. Late Caenozoic, Pebasian; Pebas (Boettger 1878), Iquitos (de Greve 1938). No other records. Diagnosis. Liris with low, well-rounded, sometimes obsoles- cent, axial folds; spiral sculpture mainly of very weak spiral threads; spire angle between 15° and 27°. DESCRIPTION. The rather high, naticoid, apex is smooth and consists of 2—2V2 whorls. Although rare individuals, including one of the paralectotypes of L. laqueata Conrad, lack axial folding, in most shells axial folding appears on the third whorl. The folds arc slightly noded at the periphery for the next four whorls or so in a minority of specimens. The number of folds varies 12-16 per whorl and their strength also varies, not only from specimen to specimen, but also in any one individual: in some cases they may be virtually obsolete. The folds die away at the lower suture and are absent from the lower half of the body whorl. Spiral sculpture is visible only on exceptionally well-preserved individuals. It consists of extremely weak threads situated mainly, but not exclu- sively, on the upper half of the whorl. A weak carination. forming a shoulder, is rarely present. Another carination at the lower suture is seen in the majority of specimens. Weak spiral threads are also found on the neck of the body whorl. The spire angle varies considerably and is not constant in individuals, decreasing with growth to give a slightly pupi- form appearance. The aperture is constricted, normally being under half the height of the last whorl. The peristome is markedly detached in some of the Iquitos shells figured by de Greve (1938), but is only slightly so in the specimens studied herein from both Pebas and Pichana. Dimensions. In mm. h br hap h/br ANSP 31397a, lectotype of 22° Turbonilla minuscula, Pebas. ANSP 31397b, paralectotype as above. NYSM 9259a, lectotype of Liris 15° laqueata Conrad, Pic
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