Development of the cranial lateral line system of Brook Trout, Salvelinus fontinalis (Teleostei: Salmonidae): Evolutionary and ecological implications.

The mechanosensory lateral line (LL) system of salmonid fishes has been the focus of comparative morphological studies and behavioral and physiological analyses of flow sensing capabilities, but its morphology and development have not been studied in detail in any one species. Here, we describe the post-embryonic development of the cranial LL system in Brook Trout, Salvelinus fontinalis, using vital fluorescent staining (4-Di-2-ASP), scanning electron microscopy, µCT, and clearing and staining to visualize neuromasts and the process of cranial LL canal morphogenesis. We examined the relationship between the timing of LL development, the prolonged life history of salmonids, and potential ecological implications.

Gross morphology of the brain and some sense organs of subterranean pencil catfishes of the genus Ituglanis Costa and Bockmann, 1993 (Siluriformes, Trichomycteridae), with a discussion on sensory compensation versus preadaptation in subterranean fishes.

Subterranean organisms provide excellent opportunities to investigate morphological evolution, especially of sensory organs and structures and their processing areas in the central nervous system. We describe the gross morphology of the brain and some cephalic sensory organs (olfactory organ, eye, semicircular canals of the inner ear) and the swim bladder (a non-sensory accessory structure) of subterranean species of pencil catfishes of the genus Ituglanis Costa and Bockmann, 1993 (Siluriformes, Trichomycteridae) and compare them with an epigean species of the genus, Ituglanis goya Datovo, Aquino and Langeani, 2016. We compared qualitatively the size of the different brain regions and sense organs of the subterranean species with those of the epigean one, searching for modifications possibly associated with living in the subterranean environment.

Anatomy, ecology, and behavior of a new species of Scleronema Eigenmann, 1917 (Siluriformes: Trichomycteridae) from coastal drainages in the southern Brazilian Atlantic Rainforest, with comments on the monophyly and phylogeny of the genus.

A new species of Scleronema (Trichomycteridae) is described from the lowlands of three coastal river basins in the Atlantic Forest of the Santa Catarina state, Southern Brazil. Aspects of the anatomy, reproduction, diet, feeding behavior and habitat of the new species are described and discussed in comparison with related taxa. The conservation status of the new species, which currently faces several threats due to environmental impacts on its region of occurrence, is established.

Ontogeny and homology of cranial bones associated with lateral-line canals of the Senegal Bichir, Polypterus senegalus (Actinopterygii: Cladistii: Polypteriformes), with a discussion on the formation of lateral-line canal bones in fishes.

The association between lateral-line canals and skull bones in fishes has been the subject of several studies and raised a series of controversies, particularly with regard to the hypothesized role of lateral-line organs (i.e. neuromasts) in osteogenesis and the consequences for hypotheses of homology of the bones associated with lateral-line canals.

Evolution of the facial musculature in basal ray-finned fishes.

Background: The facial musculature is a remarkable anatomical complex involved in vital activities of fishes, such as food capture and gill ventilation. The evolution of the facial muscles is largely unknown in most major fish lineages, such as the Actinopterygii. This megadiverse group includes all ray-finned fishes and comprises approximately half of the living vertebrate species.

The Laterosensory Canal System in Epigean and Subterranean Ituglanis (Siluriformes: Trichomycteridae), With Comments About Troglomorphism and the Phylogeny of the Genus.

The laterosensory system is a mechanosensory modality involved in many aspects of fish biology and behavior. Laterosensory perception may be crucial for individual survival, especially in habitats where other sensory modalities are generally useless, such as the permanently aphotic subterranean environment. In the present study, we describe the laterosensory canal system of epigean and subterranean species of the genus Ituglanis (Siluriformes: Trichomycteridae).