Menuites sp.

Ifrim, Christina & Stinnesbeck, Wolfgang, 2021, Ammonoids and their biozonation across the Santonian-Campanian boundary in north-eastern Coahuila, Mexico, Palaeontologia Electronica (a 34) 24 (3), pp. 1-62 : 43

Menuites sp.

Figure 34 A–D , Table 14

Material. Four specimens, CPC –2196, –2544, – 2554, and –2562 .

Description. The shells are moderately involute with a moderate expansion rate. Ornament in the inner whorls of CPC–2544 is simlar to Pachydiscus (P.) duelmensis at similar D, but ribs are more numerous and more irregular, and the shell is more involute. Each specimen presents a deep constriction.

Dimensions. Table 14.

Remarks. This morphotype differs from Menuites stephensoni by the absence of ribbing except at small diameters and by the presence of deep constrictions. The material may represent more than one species but specimens are not comparable as they represent different ontogenetic stages.

Figures

FIGURE 34. Menuites stephensoni sp. from the Tepeyac section. A–D: CPC–2196 from bed TPY69-89. Scale: 50