The lernaeopodids are highly specialized copepods which are widely distributed worldwide. In this paper the first record of Clavellisa ilishae Pillai, 1962 in the Neotropical region is documented parasitizing Sardinella brasiliensis from coastal zone of Rio de Janeiro, Brasil.

Karyotypes of two species of the African annual killifish genus Nothobranchius Peters, 1868, Nothobranchius brieni Poll, 1938 and Nothobranchius sp. from Kasenga (D.R. Congo) are described. Both species displayed diploid chromosome number 2n = 49/50 for males and females respectively with multiple-sex chromosome system type X1X2Y/X1X1X2X2. The karyotypes of studied species are considerably diff...

The fish stocking in captivity for later release into natural water bodies has historically been applied in Brazil, as a measure to mitigate impacts caused by dams. However, the released fish are adapted to the hatchery environment, which is totally different from the natural, which results in low post-release survival rates and ineffectiveness of stocking as a management measure. Worldwide, se...

Collectively, ray-finned fishes (Actinopterygii) display far more diversity in many reproductive and genomic features than any other major vertebrate group. Recent large-scale comparative phylogenetic analyses have begun to reveal the evolutionary patterns and putative causes for much of this diversity. Several such recent studies have offered clues to how different reproductive syndromes evolv...

This dataset contains information on the occurrence of Neotropical fishes (Actinopterygii, Chondrichthyes, Sarcopterygii) collected in South America, mostly from the Brazilian Amazon. The ichthyology collections of the Museu Paraense Emílio Goeldi (MPEG: http://www.museu-goeldi.br/) include specimens collected between 1900 and 2014. The dataset is now available for public consultation on the Gl...

One of the most notable features in looking across fishes is their diversity of body shape and size. Extant actinopterygian fishes range in shape from nearly spheroidal in pufferfishes to extremely elongate in snipe eels with nearly every shape in-between. One extreme along the body-shape continuum is a highly elongate form, which has evolved multiple times independently in Actinopterygii. Thus...

The actinopterygian fish †Hemicalypterus weiri Schaeffer, 1967 is herein redescribed and rediagnosed based on new information collected from reexamination of museum specimens as well as examination of recently collected specimens from the Upper Triassic Chinle Formation of San Juan County, Utah, United States. †Hemicalypterus is distinguishable by its deep, disc-shaped compressed body; ganoid-s...

The traditionally accepted relationships among basal jawed vertebrates have been challenged by some molecular phylogenetic analyses based on mitochondrial sequences. Those studies split extant gnathostomes into two monophyletic groups: tetrapods and piscine branch, including Chondrichthyes, Actinopterygii and sarcopterygian fishes. Lungfish and bichir are found in a basal position on the piscin...

Ray-finned fishes (Actinopterygii) are the dominant vertebrate group today (+30 000 species, predominantly teleosts), with great morphological diversity, including their dentitions. How dental morphological variation evolved is best addressed by considering a range of taxa across actinopterygian phylogeny; here we examine the dentition of Polyodon spathula (American paddlefish), assigned to the...

Well exposed Famennian, mainly carbonate rocks of the Bahram Formation in the vicinity of Bagher Abad village, Central Iran,yielded chondrichthyan teeth some sarcopterygii and actinopterygii teeth and fragments. Three different genera were recognizedamong the chondrichthyan teeth represented by: Phoebodus turnerae, Ph. spp., Deihim mansureae (M2, M3), Stethacanthus sp..Acanthodian and sarcopter...