Pomfrets of the High Seas

The fanfish Pterycombus petersii, photographed off the Kerama Islands by Kazuo Kayama.

The Bramidae, commonly known as pomfrets, are a cosmopolitan family of pelagic fishes, found mostly in the upper layers of the world's oceans. Pomfrets are teardrop- or elliptical-shaped, deep-bodied and strongly-compressed fish with a single long dorsal fin that is ventrally mirrored by (usually slightly shorter) similar-shaped anal fin. Some species are quite large, with about a metre as the maximum recorded length for the family (McEachran & Fechhelm 2006). Thompson (2002) stated that pomfrets feed on other fish and larger invertebrates such as squid, but García & Chong (2002) found that Brama australis fed primarily on crustaceans such as krill.


Pteraclis aesticola, photographed by Kanno Takayuki.

The Bramidae are divided between two subfamilies, Pteraclinae and Braminae, though the monophyly of the latter in particular does not necessarily appear to have been established. Pteraclinae include two genera, the fanfishes Pteraclis and Pterycombus, with particularly large triangular dorsal and anal fins. Despite their unwieldy appearance, these fins can be completely depressed into a special groove formed by modified scales running on either side of the fins, as is being done by the individual in the photo above (if expanded, the fins of Pteraclis are even more expansive than those of Pterycombus, with the dorsal fin extending all the way forward to the snout). Members of the Braminae (the genera Brama, Eumegistus, Taractes, Taractichthys and Xenobrama) have less flamboyant fins with scales running partway along the rays and unable to be depressed (Thompson 2002).


The large bramine Taractes rubescens, from here.

Phylogenetically speaking, the molecular study using by Li et al. (2009) placed the Bramidae among a clade that they referred to as Stromateoidei (though somewhat different from earlier uses of this name), that also included families such as Stromateidae (butterfishes), Scombridae (mackerels), Trichiuridae (cutlassfishes) and Chiasmodontidae (black swallowers). A comparable clade was also recovered by Yagishita et al. (2009) using different molecular markers (Li et al. used nuclear genes; Yagishita et al. used mitochondrial genes; however, Yagishita et al. sampled a smaller number of families than Li et al.). Though morphologically diverse, all families in this clade are primarily pelagic.

REFERENCES

García M., C., & J. Chong. 2002. Composicion de la dieta de Brama australis Valenciennes 1837 en la zona centro-sur de Chile (VIII región) en Otoño 2000 y Verano 2001. Gayana 66 (2): 225-230.

Li, B., A. Dettaï, C. Cruaud, A. Couloux, M. Desoutter-Meniger & G. Lecointre. 2009. RNF213, a new nuclear marker for acanthomorph phylogeny. Molecular Phylogenetics and Evolution 50: 345-363.

McEachran, J. D., & J. D. Fechhelm. 2006. Fishes of the Gulf of Mexico, vol. 2. University of Texas Press.

Thompson, B. A. 2002. Bramidae: pomfrets. In: Carpenter, K. E. (ed.) The Living Marine Resources of the Western Central Atlantic, vol. 3. Bony fishes part 2 (Opistognathidae to Molidae), sea turtles and marine mammals. FAO Species Identification Guide for Fishery Purposes and American Society of Ichthyologists and Herpetologists Special Publication 5. Food and Agriculture Organization of the United Nations: Rome.

Yagishita, N., M. Miya, Y. Yamanoue, S. M. Shirai, K. Nakayama, N. Suzuki, T. P. Satoh, K. Mabuchi, M. Nishida & Tetsuji Nakabo. 2009. Mitogenomic evaluation of the unique facial nerve pattern as a phylogenetic marker within the percifom fishes (Teleostei: Percomorpha). Molecular Phylogenetics and Evolution 53 (1): 258-266.