REVISION OF RECENT BAIRDIIDAE 61 



palp and processes barbed, none pectinate or profusedly feathered. 

 Known f ureal types have 5 long and 2 short setae {T. bradyi) or 4 

 long and 3 short setae (T. sertata). 



Affinities. — The soft-part anatomy is quite similar to that of 

 Paranesidea, which also has robust asymmetrical carapace with 

 marginal spines and exterior punctate surface. The antennal characters 

 (smooth fused claw and thickened anterodistal seta) represent an 

 approach toward the characteristic antennal features of Bairdoppilata. 



Unfortunately, no males are included in the living material available 

 for T. sertata and T. bradyi, so that, while this is the first description 

 of Triebelina anatomy, it must be confined to the female only. 



On the basis of carapace exterior, there is a strong case for retaining 

 Bairdia coronata Brady within Triebelina, but its muscle-scar pattern, 

 hingement, and appendage characters are decidedly bairdoppilatan. 



Species included. — Well-established Recent species of Triebelina 

 include the follo%ving (by original binomen) : 



Triebelina indopacifica van den Bold, 1946 



Triebelina bradyi Triebel, 1948 {—Bairdia truncata Brady, 1890) 



? Bairdia raripila Miiller, 1894 



Triebelina reticulopuncia Benson, 1959 



"f Triebelina schyroconcha, new species 



Triebelina sertata Triebel, 1948 



Bairdia tuber culata Brady, 1880 {= Bairdia rhomboidea Brady, 1869) 



Ecology. — Species of Triebelina are restricted to very shallow 

 water and are characteristic of reefs (either coralline or navigational) 

 and high wave-energy level. T. indopacifica, bradyi, sertata, and 

 tuberculata are Indo-Pacific — Red Sea in distribution and are typically 

 inhabitants of coral reef masses and talus. Similar unnamed species 

 are reported from comparable environments of Florida (Puri, 1960). 

 The probable habitat of T. reticulopuncta is the algal covering of the 

 steep rocky slopes of the coast and islands around Todos Santos Bay, 

 Baja California. If Bairdia raripila is in fact a Triebelina, then two 

 species are known from temperate latitudes. 



Triebelina sertata Triebel, 1948 



Figures 31, 326-e; Plate 2: figures 9, 10 



Triebelina sertata Triebel, 1948, p. 19, Abb. 1-2.— Key, 1953, p. 158, pi. 1: fig. 5. 

 Species BB, Haddocks, 1966, p. 48, fig. 24. 



Material. — Nosy Be; 4 adult females and several juveniles, 8 

 subfossil specimens. 



Tulear, one adult female living. 



Dimensions. — Adult female USNM 121325, right valve, length 

 0.59 mm, height 0.31 mm ; left valve, length 0.60 mm, height 0.34 mm. 



327-237 O - 69 - 5 



