Crocodylus rhombifer, Cuvier, 1807

Morgan, Gary S., Albury, Nancy A., Rímoli, Renato, Lehman, Phillip, Rosenberger, Alfred L. & Cooke, Siobhán B., 2018, The Cuban Crocodile (Crocodylus rhombifer) from Late Quaternary Underwater Cave Deposits in the Dominican Republic, American Museum Novitates 2018 (3916), pp. 1-1 : 1-

CROCODYLUS RHOMBIFER

We compared the sample of four fossil skulls of Crocodylus rhombifer from Oleg’s Bat Cave and Ni-Rahu in the Dominican Republic to modern and fossil skulls of C. rhombifer from Cuba and fossil skulls referred to this species from Abaco and Grand Cayman (see list of fossil and modern comparative cranial material of C. rhombifer in the appendix). All the cranial features described above for the fossil crocodile skulls from the Dominican Republic also characterize other West Indian samples of fossil and recent skulls of C. rhombifer . As expected, there is variation in certain cranial features, observed both within the small sample of fossil skulls from the Dominican Republic (as discussed above) and between the Dominican sample and skulls from Cuba, Abaco, and Grand Cayman. Cranial characters that show minor variation among the West Indian samples of C. rhombifer include: degree of development of the prominent ridges on the lateral edges of the cranial table on the postorbitals and squamosals (always prominent, but these ridges are better developed in some specimens than others); degree of development of the pronounced squamosal protuberances at the posterolateral corners of the cranial table (always pronounced, but these protuberances are larger in some specimens than others); location of the lateral border of the premaxillary/maxillary suture (lateral border of this suture is located anterior to the 1st maxillary tooth in some specimens, near the middle of this tooth in other specimens, and as far posterior as the posterior edge of the 1st maxillary tooth in other specimens); orientation of the premaxillary/maxillary suture (at a point about a third of the distance between the toothrow and the midline, closer to the toothrow, the premaxillary/maxillary suture takes a slight excursion either anteriorly to a point slightly anterior to the alveolus of the 1st maxillary tooth or posteriorly to a point corresponding to the middle of the 1st maxillary tooth); and the number of maxillary teeth (13 teeth in the majority of specimens, but 14 teeth are present in one skull from Oleg’s Bat Cave and a skull from Abaco, while another skull from Abaco has only 12 teeth).

The primary difference among the fossil samples of Crocodylus rhombifer from the Dominican Republic, Cuba, Abaco, and Grand Cayman is the overall size of individuals (measurements of skulls in table 1; of limb bones in table 2). The largest skulls of C. rhombifer are from Cuba, with two fossil skulls from the Ciego Montero spring deposit representing the largest known individuals of this species, living or fossil. The total length of the skull in modern specimens of C. rhombifer from Cuba averages 390 mm (observed range, 346–475 mm; 3 individuals, 2 from the Zapata Swamp, 1 captive). The total length of the skull in Late Quaternary specimens of C. rhombifer from Ciego Montero in Cuba averages 513 mm (observed range, 382–653 mm; 3 individuals). The skulls of C. rhombifer from the three other islands are considerably smaller than the skulls from Cuba. The fossil crocodile skulls from the Dominican Republic (Hispaniola) have a mean total skull length of 302 mm (observed range, 271–349 mm; 3 individuals). The fossil skulls of C. rhombifer from Abaco are somewhat smaller on average, with a mean total skull length of 286 mm (observed range, 243–361 mm; 12 adult individuals), although the largest skull from Abaco (361 mm) is slightly larger than the largest skull from