Ontogenic events and swimming behavior of larvae of the characid fish Salminus brasiliensis (Cuvier) (Characiformes, Characidae) under laboratory conditions

The larval ontogeny and swimming behavior of the characid fish Salminus brasiliensis (Cuvier, 1816) were studied under experimental laboratory conditions, from hatching to yolk absorption. At day 1, the larvae were transparent, with sparse dendrite chromatophores and a well-developed adhesive organ on the head. The retinal epithelial cells were initiating pigmentation. The branchial arches were at the initial phase of differentiation. The larvae were able to perform only vertical displacements and, when resting on the tank bottom, remained in lateral decumbency, in groups of 3 to 15 larvae. On day 2, the mouth was open, with conical teeth, and the digestive tube presented lumen and folded mucosa. The gaseous bladder and pectoral fins also were in differentiation. The larvae performed vertical and horizontal movements, adhered to the water surface by means of the adhesive organ or formed groups of three to six on the tank bottom. On day 3, the adhesive organ turned dorsal, the retina was pigmented, the digestive tube mucosa showed goblet cells, and the yolk sac exhausted. The larvae were now scattering in the water column forming no groups on the bottom

Reproduction of the catfish Iheringichthys labrosus (L\ufctken) (Pisces, Siluriformes) in Furnas reservoir, Minas Gerais, Brazil

The reproductive biology of Iheringichthys labrosus (Lütken, 1874) was studied in Furnas reservoir, Minas Gerais, Brazil. The fishes, 323 males and 817 females, were captured bimonthly from August 1993 to July 1994 by using gill nets with 3-10 cm mesh size. Gonadal maturation of the specimens was analyzed through macro and microscopical characteristics of the gonads. The secretory activity of the tubules of the caudal region of the testis was analyzed during the maturational testicular cycle. Females and males were in reproductive activity throughout the year in the reservoir. The peak of advanced maturation/mature stages occurred from October to January and of spawned/spent from February to May. The spawning of I. labrosus was identified as fractional or multiple type: occurring in the reservoir or in tributaries around it. The oocyte development of the species was asynchronous as different clusters of oocytes occurred simultaneously in the ovarian parenchyma. The epithelium of the tubules of the caudal region of the testis was in high secretory activity during advanced maturation/mature stage and this activity was absence in resting. The gonadosomatic index followed gonadal maturation, and the hepatosomatic index of females was lowest in advanced maturation/mature probably due the contribution of the liver in the vitellogenesis. The variations of the stomach repletion index, coelomic fat and condition factor indicated that the feeding activity was reduced and that the energetic reserves were consumed during the reproductive period.A biologia reprodutiva de Iheringichthys labrosus (Lütken, 1874) foi estudada no reservatório de Furnas, Minas Gerais, Brasil, utilizando-se técnicas biométricas, macroscópicas e microscópicas. Capturaram-se, bimestralmente, 323 machos e 817 fêmeas, utilizando-se redes de emalhar no período de agosto de 1993 a julho de 1994. A atividade secretora dos túbulos da região caudal dos testículos foi analisada durante o período reprodutivo. Machos e fêmeas encontravam-se em atividade reprodutiva durante todo ano com pico de maturação avançada/maduro de outubro a janeiro de desovado/espermiado de fevereiro a maio. O longo período de desova e a alta freqüência de fêmeas parcialmente desovadas indicaram que a espécie tem desova do tipo parcelado, com desenvolvimento assincrônico dos ovócitos. A espécie desova no reservatório e/ou em tributários nas suas proximidades. O epitélio dos túbulos da região caudal dos testículos apresentou alta atividade secretora durante o estádio maturação avançada/maduro, estando essa atividade ausente no estádio de repouso. O índice gonadossomático acompanhou a maturação das gônadas e o índice hepatossomático apresentou-se mais baixo na maturação avançada/maduro, sugerindo transferências de substâncias hepáticas para os ovários. As variações dos índices de repleção do estômago, de gordura celômica e o fator de condição indicaram que os peixes alimentam-se menos e consomem reservas graxas no período reprodutivo

Long-term avifaunal survey in an urban ecosystem from southeastern Brazil, with comments on range extensions, new and disappearing species

Urban avifaunal surveys in Brazil have been increasing in recent years, despite none of them consisting of long-term studies indicating events of regional colonization and/or missing species. Here, we present an avifaunal survey of an urbanized ecosystem in southeastern Brazil, carried out along 30 years, on the campus of the Pontifícia Universidade Católica de Minas Gerais, municipality of Belo Horizonte, Minas Gerais state. Inside the campus there is a forest reserve adjacent to a small lake. The inventory was mainly based on opportunistic records from the years 1982-2013. We recorded 134 bird species along the past 30 years. However, the present avifauna is composed of 123 species. A total of 97 species was recorded in the reserve, including the forest fragment and the adjacent lake, of which 44 were exclusive to this area. Nevertheless, the majority of the current species found in the study area is forest independent (N = 51) or semi-dependent (N = 46). There is a predominance of insectivorous (N = 43) and omnivorous (N = 29) species. The current avifauna is represented by 15 migratory species, which can be found both in the urbanized area and in the forest remnant. However, the majority of the species (N = 75) is resident in the area, including three invasive species, whereas few others (N = 28) are occasional visitors. The remaining species were probably introduced in the area. There were 11 cases of disappearing species, which include typical forest birds, and also species typical of wetlands and rural environments. We also comment on recent colonization and on the possible effects of isolation on birds. Probably, the majority of forest-dependents are on the brink of extinction in the forest fragment. Thus, the species' list provided here can be useful as a database for monitoring long-term effects of urbanization on this bird community