Relationship between morphology and diets of six neotropical loricariids

Abstract

Most loricariids are algivorous and detritivorous and play an important role in both the grazer and detritus food chains of neotropical waters. Relationships between morphological variation and diet were analysed in six syntopic species (Rhinelepis aspera, Hypostomus regani, H. ternetzi, H. margaritifer, H. microstomus and Megalancistrus aculeatus) fished commercially in a 10 km 2 area of the Upper Paraná River upstream from the Itaipu Reservoir. Species feeding on fine grained detritus use suction to obtain food, and possess a well-developed respiratory membrane, long gill rakers, rudimentary labial and pharyngeal teeth, a thin stomach wall, and a long intestine. Species feeding on coarser material (e.g. periphyton), ingest food by scraping the substratum. Their morphological characteristics are large, strong, spatulate teeth, short gill rakers, a well-developed stomach, and a shorter intestine. The first species group is composed by R. aspera while the latter by M. aculeatus and H. microstomus. The others species had an intermediary position. 2001 The Fisheries Society of the British Isles

Dietary-morphological relationships in fish assemblages of small forested streams in the Bolivian Amazon

“…This appears to be a highly robust ecomorphological pattern since our finding is in agreement with results found in several other studies dealing with fish assemblages worldwide (Kotrschal 1989;Paugy 1994;Kramer and Bryant 1995;Hugueny and Pouilly 1999;Winemiller and Adite 1997;Delariva and Agostinho 2001;Pouilly et al 2003;Ward-Campbell et al 2005). Bowen (1983) working on neotropical fish communities ranked relative intestine development in relation to diet as: carnivorous<omnivorous<herbivorous<detritivorous, which is generally interpreted as reflecting the resistance of different foods to digestion (Herder and Freyhof 2006).…”

“…For instance, in fishes, gut length clearly distinguish algivores, detritivores and herbivores from carnivores (Paugy 1994;Kramer and Bryant 1995;Delariva and Agostinho 2001;Ward-Campbell et al 2005). However, relationships between diet and morphology are equivocal since other studies found weak and indistinct results rather relating feeding and morphological variables to local environmental factors and resource availability (Grossman 1986;Motta 1988;Douglas and Matthews 1992;Winemiller and Adite 1997;Bellwood et al 2006).…”

Evolution of long-toothed fishes and the changing nature of fish–benthos interactions on coral reefs

“…Scale bars represent 500 mm, 100 mm and 500 mm, respectively. NATURE COMMUNICATIONS | DOI: 10.1038/ncomms4144 ARTICLE flexible, elongate, closely spaced teeth [32][33][34][35][36] , similar to those seen in specialized detritivores on coral reefs. The similarity in morphology between marine and freshwater groups reflects a common challenge, selectively removing fine particulate material from algal turfs on a hard substratum (the epilithic algal matrix, EAM on reefs 37 and aufwuchs in the African rift lakes 33 ).…”

Reproductive biology and feeding of Curimatella lepidura (Eigenmann & Eigenmann) (Pisces, Curimatidae) in Juramento reservoir, Minas Gerais, Brazil

“…As an adaptation to the iliophagous habit, the digestive tract of C. lepidura presents a mechanic stomach similar to gizzard and long-coiled intestine for a better utilisation of food and does not present teeth in the maxillary (AGOSTINHO et al 1997, GOMES & VERANI 2003. Moreover, the long coiled intestine found in C. lepidura is characteristic of the detritivorous fish, being intestine length related directly to food digestibility and quantity of detritus (DELARIVA & AGOSTINHO 2001).…”