Morphological and sensory specializations of five New Zealand flatfish species, in relation to feeding behaviour

Abstract

The morphology of the feeding apparatus and sensory systems of flatfish species Rhombosoleu plebeiu (Richardson, 1843). Rhombosolea leporinu Gunther, 1862, Pelrorhumphus novuezeelandiue Gunther, 1862, Pelorreris flavilutus Waite, 191 1 (f. Pleuronectidae) and Arnoglossus scuphu (Forster, in Bloch & Schneider, 1801) (f. Bothidae) are described. The four pleuronectid species have asymmetric jaws and non-toothed gill rakers typical of benthic-feeding flatfish, while the bothid has symmetric jaws and toothed gill rakers typical of midwater-feeding flatfish. R. plebeia, R. leporinu and P. novuezeelundiue have extensive external taste bud systems which facilitate non-visual prey location. External tastebuds are lacking in P.fluvilurus and A. scuphu; however, these two species have relatively large, prominent eyes which facilitate visual prey location. The lateral line is well-developed in all five species, but R . plebeiu. R. Ieporinu and particularly P. novuezeelundiae have additional free neuromasts on their blind sides, which probably assist in prey location.The feeding habits of these flatfish species closely reflect their morphological and sensory specializations. A detailed feeding study in Wellington Harbour, New Zealand showed that R. plebeiu, R. leporinu and P. novuezeelundiue have closely overlapping diets consisting of largely sedentary or inactive invertebrates living in the bottom sediments. In contrast, P.j?avilurus and A. scupha have specialized diets of one or two species only. While the latter two species differ in that P.Juvilurus is a benthic feeder and A. scuphu is pelagic feeder, both are visual feeders and therefore more specialist than the other three species.

Feeding in the dark: lateral-line-mediated prey detection in the peacock cichlid Aulonocara stuartgranti

“…Nevertheless, the presence of morphological and physiological specializations of individual sensory systems (e.g. Livingston, 1987;Schwarz et al, 2011) is traditionally used as an indication of the enhancement of behavioral capabilities. This correlation provides evidence for adaptive evolution, but the link between sensory morphology and prey detection behavior is not always clear.…”

Quantitative differences in the chemoreceptor systems in the barbels of two species of Mullidae (Mullus surmuletus and M. barbatus) with different bottom habitats

“…Less is known of the relationships between the morphology of the chemoreceptors and the environment in marine non-ostariophysi teleosts. Studies have focused on solitary chemosensory cells (Kotrschal 1992(Kotrschal , 1995, the sensory pores of the dorsal radii of Pleuronectiformes (Appelbaum et al 1983, Livingston 1987, and recently on the hyoid barbels of the Mullidae family (McCormick 1993).…”

Anomalies in the cephalic area of laboratory-reared larvae and juveniles of the common sole, Solea solea: oral jaw apparatus, dermal papillae and pigmentation

“…Oral jaws with a similar degree of asymmetry are described for its sister group, the Cynoglossidae (Chapleau 1988) and for some IndoPacific species of the subfamily Rhombosoleinae (Pleuronectidae). In these two groups, the jaw apparatus has the same form and function, closely related to the benthic feeding behaviour of juveniles and adults (Holmes & Gibson 1983, Livingston 1987. The ontogeny of dentition in soles seems little documented.…”