84 U.S. NATIONAL MUSEUM BULLETIN 29 5 



Affinities. — Bairdoppilatan dentition is present although too 

 fine to be drawn to scale. Otherwise the species is not sufficiently- 

 distinctive to be named at this time. 



Bairdoppilata {Glyptobairdia) Stephenson, 1946 



Glyptobairdia Stephenson, 1946, p. 345. — not Pokorny, 1958, p. 226. 



Type-species. — Bairdia coronata Brady, 1870, p. 243, pi. 32: fig. 9 

 {= Glyptobairdia hermudezi Stephenson, 1946, p. 346, pi. 43, figs. 1-3). 



Diagnosis. — Carapace externally ornamented with ridges and 

 pitting. Hinge very robust, with crenulate groove and raised terminal 

 teeth in right valve, incised crenulate bar and sockets in left valve; 

 anterior and posterior segments Avith auxiliary bairdoppilatan denticles 

 and sockets conspicuously developed. Appendages as in B. (Bair- 

 doppilata) . 



Affinities. — Glyptobairdia has for some years been considered as 

 a subjective synonym of Triebelina but is technically available.This 

 name is resurrected here to emphasize and express more accurately 

 the uniqueness and bairdoppilatan affinity of Bairdia coronata Brady, 

 the type-species and at present the only Recent species assignable 

 to this subgenus. 



Bairdoppilata (G.) coronata (Brady) resembles Triebelina in such 

 characters as carapace robustness, external ornament, outhne, and 

 marginal denticles; however, it differs conspicuously in liingement, 

 muscle-scar pattern, and appendage characters, which are those of 

 Bairdoppilata. It seems to be the only living species of a morphologic 

 type that is represented as early as the Triassic by such genera as 

 Carinobairdia. KoUmann (1960, 1963) stated that Glyptobairdia 

 should be revived for the Recent representative of a lineage that is 

 distinct from and has coexisted with the Triebelina lineage at least 

 since the Rhaetian. Unfortunately, the hingement of these Triassic 

 species has not been described, but the exterior ornament is clearly 

 related to that of B. (G.) coronata. 



Bairdoppilata (Glyptobairdia) coronata (Brady), 1870 



Figure 44o-3 



Bairdia coronata Brady, 1870, p. 243, pi. 32: fig. 9. 



Triebelina coronata (Brady) of Stephenson, 1947, p. 578.— Puri, 1963, p. 131, 



pi. 6: figs. 1, 2.— Morkhoven, 1958, p. 366, pi. 46: figs. 1-6.— Rome, 1960, 



pp. 1-14. 

 Glyptobairdia bermudezi Stephenson, 1946, p. 346, pi. 42, figs. 1-3. 



Material. — One male and two females living in Andros sample 34 

 from the Bahamas; known also from personal collections on the south 

 shore of Bermuda. 



