Trophic ecomorphology of cardinalfish

Abstract

Trophic diversity in 9 cardinalfish species was investigated by comparing 14 morphological characteristics of their feeding apparatus with dietary data based on stomach content analysis. Analysis of the morphological characteristics separated the 9 species into 3 distinct groups. The first group (Cheilodipterus macrodon, C. artus and C. quinquelineatus) was characterized by elongated heads; the second group (Archamia fucata, Apogon guamensis, A. cyanosoma and A. fragilis) by large gapes; and the third group (Apogon exostigma, A. doederleini) by wider heads and low transmission coefficient in their jaw mechanics. Stomach samples, however, revealed that morphology was of limited utility in predicting dietary groupings. The majority of species examined displayed generalist diets. The results indicate that while morphology may predict feeding potential, or feeding mode, actual resource use in this group may be shaped primarily by other modifying factors such as behaviour and prey availability. In contrast to other reef fish groups, morphology does not appear to play a strong role in influencing diet in the Apogonidae.

To feed or to breed: morphological constraints of mouthbrooding in coral reef cardinalfishes

“…Between 6 and 20 brooding males (mean ¼ 13 individuals) from seven cardinalfish species were collected, as described above. These species encompassed three broad trophic morphologies: a largely piscivorous group with elongate heads and snout (C. artus, C. macrodon and C. quinquelineatus); a generalist invertebrate feeding group with large gapes (A. fucata, O. cyanosoma and Z. fragilis); and a generalist invertebrate feeding group with wide heads (A. doederleinii; [25]). An absence of brooding male P. exostigma and N. fusca at the time of the study precluded analyses for these species.…”

“…Nine species of cardinalfish (Archamia fucata, Apogon doederleinii, Cheilodipterus artus, Cheilodipterus macrodon, Cheilodipterus quinquelineatus, Nectamia fusca, Ostorhinchus cyanosoma, Pristiapogon exostigma and Zoramia fragilis) were selected as they were locally abundant at the study site, and encompassed broad taxonomic, phylogenetic, morphological and trophic variation [24][25][26][27][28][29]. These species also spanned the maximum range of body sizes of species recorded from the GBR [30].…”

“…Within approximately 2 h of capture (i.e. while fresh and relaxed), each specimen was weighed and a series of external measurements recorded; standard length, snout length, head length and width, horizontal gape, vertical gape, upper jaw protrusion and lower jaw protrusion (see Barnett et al [25] for detailed descriptions). The visceral cavity was dissected open and the sex of each specimen determined by macroscopic examination of the gonads.…”

“…The objective of this study, therefore, was to examine the potential functional implications of mouthbrooding in coral reef cardinalfishes (Family Apogonidae). Cardinalfishes are a species-rich and abundant group of primarily marine fishes, in which all species are paternal mouthbrooders that display moderate trophic and morphological diversity [25]. Unlike the mouthbrooding cichlids in which the functional decoupling of the oral and pharyngeal jaws may mask the functional constraints of mouthbrooding, cardinalfishes have a generalized percomorph branchial basket and do not possess welldeveloped pharyngeal jaws or dentition.…”

Habitos alimentarios e interacciones troficas de Anisotremus interruptus (Pisces: Haemulidae) y Lutjanus argentiventris (Pisces: Lutjanidae) en el Pacifico central mexicano

“…Aunque la LT de las dos especies es similar y comparten los mismos sitios de alimentación, la dieta resultó ser distinta debido a diferencias en la morfología y tamaño de la boca. Estas diferencias están relacionadas directamente con el tamaño de los depredadores y la apertura de la boca (Barnett et al, 2006;Takeuchi, 2008).…”