966 



W. O. CERNOHORSKY 



Méth., Kiener's delineation (pl. 19, fig. b) shows some resemblance to the lectotype, 

 except that the spécimen figured appears more slender and the whorls less angulate. 

 The lectotype has 8 angulate whorls and a missing protoconch; it is brown in 

 colour, ornamented with 2 white spiral bands on the body whorl and a single band 

 on earlier whorls; Sculpture consists of 12 axial ribs on the body whorl and 16 on 

 the penultimate whorl; interstices have incised spiral grooves, and the siphonal 

 fasciole spiral cords. The aperture is narrow, lirate within, pariétal wall is calloused 

 and the columella has 4 prominent folds. 



The taxonomic status of Mitra costellaris is somewhat complicated. Gmelin 

 (1791), described a Voluta subdivisa, which he based on a previous description and 

 illustration in Chemnitz (1788, Vol. 10, p. 171, pl. 151, figs. 1434-37). Gmelin's 

 cited figures represent two distinct species, and Rôding (1798), was the first author 

 to restrict Gmelin's V. subdivisa to figures 1436-37 delineated on plate 151. Due to 

 Roding's restriction, Mitra costellaris Lamarck, is a synonym of Voluta subdivisa, 

 and Mitra lyrata (Lamarck, 1822), is applicable to the species depicted in figures 

 1434-35 on plate 151. 



Vexillum subdivisum (Gmelin) has been recorded from the Western Pacific and 

 East Indian Océan région. 



Mitra nigrina Lamarck, 1811 

 (Fig. 18) 



1811. Mitra costellaris var. B, M. nigrina Lamarck, Ann. Mus. d'Hist. Nat., 

 17:206, No. 25 



L'Océan indien; mon cabinet. 



Lamarck appended the name M. nigrina to the var. B of M. costellaris. 

 Lamarck's description, short as it may be, is applicable to the form of M. costellaris 

 with less pronounced, smaller axial ribs. The holotype No. 1102/56/2: 39.7 x 

 13.1 x22.2 mm, is a form of M. costellaris with finer and more numerous axial ribs 

 on the early whorls; on the body whorl, the axial ribs tend to become obsolète on 

 the ultimate half of the whorl, and less nodulose on the presutural ramp. The spiral 

 cords on the siphonal fasciole are less prominent. 



Mitra lyrata Lamarck, 1822 

 (Fig. 19) 



1798. Tabl. Encycl. Méth., pl. 373, figs. 1 a, b 



1811. Mitra subdivisa Lamarck, Ann. Mus. d'Hist. Nat., 17:206, No. 26 (non 

 Voluta subdivisa Gmelin, 1791) 



1822. Mitra lyrata Lamarck, Anim. s. vert., 7:308 



