Spawning behavior of garden eels, Gorgasia preclara and Heteroconger hassi (Heterocongrinae), observed in captivity.
Marine Behaviour and Physiology 48(5). DOI:10.1080/10236244.2015.1064213
The behavior and reproductive ecology of typically nocturnal marine eels is poorly known but garden eels (Congridae, Heterocongrinae) are familiar tropical marine eels. They live in colonies and protrude their bodies from burrows during the daytime to feed on zooplankton. Apparent daytime courtship/spawning-like behavior has been observed within the colonies but actual spawning and fertilized egg production has not been confirmed. This study describes observations of splendid garden eels (Gorgasia preclara) and spotted garden eels (Heteroconger hassi) spawning in low light at night and producing fertilized eggs in a large multispecies public-display tank in the Sumida Aquarium. Video recordings of 5 of 17 detected spawning or egg or sperm release events documented the spawning behavior of G. preclara, and positively buoyant fertilized eggs of both species were collected. Their spawning behavior while protruding from widely spaced burrows confirms that garden eels likely spawn within their colonies with their pelagic eggs drifting away with currents.
On the occurrence of three non-native cichlid species including the first record of a feral population of Pelmatolapia (Tilapia) mariae (Boulenger, 1899) in Europe.
Royal Society Open Science 4(5). Published:21 June 2017. https://doi.org/10.1098/rsos.170160
Thermally influenced freshwater systems provide suitable conditions for non-native species of tropical and subtropical origin to survive and form proliferating populations beyond their native ranges. In Germany, non-native convict cichlids (Amatitlania nigrofasciata) and tilapia (Oreochromis sp.) have established populations in the Gillbach, a small stream that receives warm water discharge from a local power plant. Here, we report on the discovery of spotted tilapia (Pelmatolapia mariae) in the Gillbach, the first record of a reproducing population of this species in Europe. It has been hypothesized that Oreochromis sp. in the Gillbach are descendants of aquaculture escapees and our mtDNA analysis found both O. mossambicus and O. niloticus maternal lineages, which are commonly used for hybrids in aquaculture. Convict cichlids and spotted tilapia were most probably introduced into the Gillbach by aquarium hobbyists. Despite their high invasiveness worldwide, we argue that all three cichlid species are unlikely to spread and persist permanently beyond the thermally influenced range of the Gillbach river system. However, convict cichlids from the Gillbach are known to host both native and non-native fish parasites and thus, non-native cichlids may constitute threats to the native fish fauna. We therefore strongly recommend continuous monitoring of the Gillbach and similar systems.
A review of the leucogaster species complex of the Indo-Pacific pomacentrid genus Amblyglyphidodon, with descriptions of two new species.
aqua, J. Ichthyol. Aquat. Biol. 5(4):139-152.
Bisher wurde angenommen, dass der indo-pazifische Pomacentride Amblyglyphidodon leucogaster aus verschiedenen, geografischen Farbvarianten bestesteht. Die vorliegende Untersuchung deutet jedoch auf einen aus vier Arten bestehenden Komplex hin: A. leucogaster (Bleeker) aus dem westlichen Pazifik und ostlichen Randgebiet des indischen Ozeans; A. orbicularis (Hombron u. Jacquinot) von Samoa, Fiji und Neu Kaledonien und zwei hier neu beschriebene Arten - A. indicus vom Roten Meer und Indischenr Ozean und A. melanopterus von Tonga. Die einzelnen Arten des leucogaster-Komplexes unterscheiden sich hautsachlich durch Kombinationen von Farbmustern und Anzahl der Kiemenreusen. Ein Bestimmungsschlussel fur Amblyglyphidodon-Arten liegt bei.
Four new species of Cyprinodon from southern Nuevo León, Mexico, with a key to the C. eximius complex (Teleostei: Cyprinodontidae).
Ichthyological Explorations of Freshwaters, 4(4):295-308.
Four New Pupfishes of the Genus Cyprinodon from Mexico, with a Key to the C. eximius Complex.
Bull. Southern California Academy of Sciences 75(2): 68-75.
The pupfishes (genus Cyprinodon) referable to the C. eximius complex comprise seven species that are restricted to, or had their origin in, the Chihuahuan Desert region of Mexico and adjacent parts of Texas and New Mexico. Four are described as new; the remainder are C. eximius, C. atrorus, and C. latifasciatus. Most are of restricted distribution; one is extinct and another may be. Keys, diagnoses, and ranges are given for each species and all are illustrated. The distinctive morphometric characters of the new species are given. Life colors and color patterns are important in distinguishing species
Natural genetic polymorphism and phylogeography of Siberian sturgeon Acipenser baerii Brandt, 1869.
Russ. J. Genet. 53: 358–368. https://doi.org/10.1134/S1022795417030024
Five populations of Siberian sturgeon Acipenser baerii collected throughout the species distribution range (Lake Baikal, Lena, Yenisei, Kolyma, and Irtysh rivers) were examined for genetic polymorphism using five tetraploid microsatellite loci and the mitochondrial DNA control region. It was demonstrated that Siberian sturgeon was represented by genetically well-differentiated groups that corresponded to hydrographic basins, Ob–Irtysh, Baikal–Yenisei, Lena, and Kolyma. Population assignment of the Siberian sturgeon broodstock should be considered in the restocking programs.
A phylogenetic analysis of Brycon and Henochilus (Characiformes, Characidae, Bryconinae) based on the mitochondrial gene 16S rRNA.
Genetics and Molecular Biology, 31 (1, suppl): 366-371
The genus Brycon, the largest subunit of the Bryconinae, has 42 valid species distributed from southern Mexico to the La Plata River in Argentina. Henochilus is a monotypic genus, comprising a single species (H. wheatlandii) found in the upper Rio Doce basin. In the present study, partial sequences of the mitochondrial gene 16S were obtained for fifteen species of Brycon and for Henochilus wheatlandii. The results showed that the genus Brycon is paraphyletic, since Henochilus is the sister-group of B. ferox and B. insignis. The most basal species analyzed were the trans-Andean species B. henni, B. petrosus, and B. chagrensis.
The endangered species Brycon orbignyanus: genetic analysis and definition of priority areas for conservation.
Environ Biol Fish 98: 1845–1855. https://doi.org/10.1007/s10641-015-0402-8
Currently, biodiversity is threatened by several factors often associated with human population growth and the extension of areas occupied by human activity. In particular, freshwater fish fauna is affected by overfishing, deforestation, water pollution, introduction of exotic species and habitat fragmentation promoted by hydroelectric dams, among other environmental impact factors. Several action plans to preserve ichthyofauna biodiversity have been adopted; however, these plans frequently cover only a small number of species, and decisions are often made without strong scientific support. This study aimed to evaluate the genetic aspects of wild groups of Brycon orbignyanus, an endangered fish species, using microsatellites and D-loop regions to identify the genetic structure of the samples and to establish priority areas for conservation based on the genetic patterns of this species. The results indicated that the samples showed levels of genetic variability compatible with others studies with Neotropical fishes. However, the results obtained in the analysis of molecular variance (AMOVA) for microsatellites (F ST = 0.258) and D-loop (F ST = 0.234) and the interpopulation fixation index revealed that B. orbignyanus was structured in different subpopulations in the La Plata River basin; the areas with better environmental conditions also showed subgroups with higher rates of genetic variability. Future conservation actions addressing these sites should consider two different management units: the complex formed by the Ivinhema River, Upper Paraná, Camargo Port and Ilha Grande groups; and the complex formed by the Verde River and Sucuriu River groups.
Revision of the extant Polypteridae (Actinopterygii: Cladistia).
Ichthyological Exploration of Freshwaters. July 2019: 1-96. DOI:10.23788/IEF-1094
The species-level taxonomy of all extant members of the family Polypteridae is revised. Two genera are recognised: Polypterus and the monotypic Erpetoichthys. Thirteen species of Polypterus are regarded as valid: P. bichir (type species), P. ansorgii, P. congicus, P. delhezi, P. endlicherii, P. mokelembembe, P. ornatipinnis, P. palmas, P. polli, P. retropinnis, P. senegalus, P. teugelsi and P. weeksii. Polypterus lapradei and P. bichir katangae are considered junior synonyms of P. bichir. Polypterus senegalus meridionalis is synonymized with P. senegalus, and P. buettikoferi and P. retropinnis lowei are regarded as junior synonyms of P. palmas. Lectotypes of P. ansorgii, P. congicus and P. delhezi are designated. Distribution maps for each species are compiled and a key for all species of Polypteridae is provided.
First observation of Salaria fluviatilis in Lake Geneva / Premier signalement de Salaria fluviatilis dans le lac Leman.
Cybium, International Journal of Ichthyology 34(4): 401-402.
En mai 2010, une campagne de pêches électriques dans trois secteurs littoraux espacés de plusieurs dizaines de kilomètres le long de la rive française du lac Léman a abouti à la capture systématique de blennies fluviatiles, Salaria fluviatilis (Asso,1801), dont c'est le premier signalement dans le lac.
In May 2010, a fishing campaign by electricity on three distant sites along the French side of the lake Geneva provided regular catches of freshwater blennies, Salaria fluviatilis (Asso, 1801). This is the first record of the species in this lake.