First record of the non-native pacu, \u3cem\u3ePiaractus brachypomus\u3c/em\u3e, in Lago Petén-Itzá, Guatemala, Central America

We documented the first record of the non-native species Piaractus brachypomus (Characiformes: Serrasalmidae) in Lago Petén-Itzá, Petén, Guatemala. One brined specimen was donated by a local fisherman in San Benito, El Petén. The captured specimen was reportedly collected in the southern basin of the lake. We used the mitochondrial gene cytochrome oxidase I (COI) to validate identity of the specimen. We hypothesize that the local aquarium trade is the most likely source of introduction of the non-native Pacu in Lago Petén-Itzá. Documentamos el primer registro de la especie no nativa Piaractus brachypomus (Characiformes: Serrasalmidae) en el lago Petén Itzá, Petén, Guatemala. Un espécimen colectado en la cuenca sur del lago por pescadores locales de San Benito, Petén nos fue donado. La identificación a nivel de especie fue realizada utilizando el gen mitocondrial citocromo oxidasa I (COI). Hipotetizamos que individuos provenientes de acuarios ornamentales son la fuente más plausible de la introducción del pez no nativo Pacu en el lago Petén Itzá

Objectively measuring subjectively described traits: Geographic variation in body shape and caudal coloration pattern within vieja melanura (Teleostei: Cichlidae)

© 2017, Universidad de Costa Rica. All rights reserved. Vieja melanura is a Neotropical cichlid occurring in the Petén-lake district systems of Guatemala, as well as the Río Grijalva-Usumacinta basin, and other systems in Southern México, Belize, and Guatemala. A caudal stripe, extending forward from the caudal peduncle, is characteristic of this species. This stripe is sloped downward in nearly all individuals of V. melanura, but the degree of the slope is highly variable throughout its range. The slope and shape of the stripe has previously been used in diagnosing and differentiating between species of Vieja. The purpose of this study was to use objective methods to investigate morphological variation in the caudal stripe and body shape throughout the range of V. melanura. We studied geometric morphometric analyses of body shape and empirical measurements of the slope of the caudal stripe in 215 specimens of V. melanura. We also used the mitochondrial cytochrome b marker to study population level patterns within V. melanura. Results from our analyses showed significant geographic variation in body shape and patterns of coloration with little mitochondrial phylogeographic structure. These patterns likely correspond to differences in riverine habitats throughout the species’ distribution. In conclusion, these results can be used to inform other studies of color and shape variation as it applies to taxonomy and systematics

Derivation of the freshwater fish fauna of Central America revisited: Myers\u27s hypothesis in the twenty-first century

© The Willi Hennig Society 2014. Although attempts to understand Central American freshwater fish provincialism date to the 1960s, early efforts lacked the wealth of distributional data now available. Biogeographic work on Central American freshwater fishes has been largely descriptive and regional, and lacked a broader synthesis. Here we use parsimony analysis of endemicity (PAE) to elucidate faunistic relationships between major drainages and to delineate areas of endemism. We then perform a Brooks parsimony analysis (BPA) on the resulting areas. The PAE recovered a primary division between four Pacific and six Atlantic slope areas of endemism. In contrast, the BPA recovered two Central American geographic clades, one sharing a history with North America and the other with South America. Fish diversity is uneven across Central America, with greater diversity in areas adjacent to the more species-rich regions of North and South America. In northern and nuclear Central America, the paucity of ostariophysan freshwater fishes such as catfishes and characins (groups that dominate adjacent regions) contrasts with high species richness of poeciliids and cichlids. Results of this study are consistent with Myer\u27s hypothesis that poeciliids and cichlids dispersed to Northern or Nuclear Middle America early in the Cenozoic, long before the Plio-Pleistocene rise of the Isthmus of Panama

Climate change models predict decreases in the range of a microendemic freshwater fish in Honduras

Despite their incredible diversity, relatively little work has been done to assess impacts of climate change on tropical freshwater organisms. Chortiheros wesseli is a species of Neotropical cichlid (Cichlidae: Cichlinae) restricted to only a few river drainages in the Caribbean-slope of Honduras. Little is known about this species and few specimens had been collected until recently; however, our work with this species in the wild has led to a better understanding of its ecology and habitat preferences making it an excellent model for how freshwater fishes can be affected by climate change. This study assesses the distribution and habitats of Chortiheros wesseli using a combination of field data and species distribution modeling. Results indicate this species is largely limited to its current range, with no realistic suitable habitat nearby. Empirical habitat data show that this species is limited to narrow and shallow flowing waters with rapids and boulders. This habitat type is highly influenced by precipitation, which contributed the greatest influence on the models of present and future habitat suitability. Although several localities are within boundaries of national protected areas, species distribution models all predict a reduction in the range of this freshwater fish based on climate change scenarios. The likelihood of a reduced range for this species will be intensified by adverse changes to its preferred habitats

First record of the non-native suckermouth armored catfish \u3cem\u3eHypostomus cf. niceforoi\u3c/em\u3e (Fowler 1943) (Siluriformes: Loricariidae) from Central America

We document the first record of Hypostomus cf. niceforoi in Central America. Two specimens of these suckermouth armored catfishes were collected in Lake Nicaragua (Nicaragua) and identified as H. cf. niceforoi. Hypostomus niceforoi is endemic to Andean streams of Colombia, Venezuela, Ecuador, and Peru. We hypothesize that its introduction in Central America is related to the aquarium trade, as is the case of other armored catfish species introductions

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Diversification and Biogeography of Neotropical Cichlids

The diversity of fishes in the Neotropics consists of nearly 6,000 species, approximately 10% of all vertebrate species on the planet. Evolutionary patterns and processes in fishes are often quite distinct from terrestrial biota, and the study of freshwater fishes can offer insight into understanding evolution and biogeography of regions. One of the major lineages of neotropical freshwater fishes, family Cichlidae, consist of over 500 species in the Neotropics but over 1,600 species overall. The aim of this study is to (1) assess diversification patterns within the family, with a focus on neotropical clades, (2) reassess phylogenetic relationships among northern Middle American cichlids and formally revise the taxonomy of this enigmatic group of fishes, and (3) assess phylogeographic structure within widespread Middle American fishes and begin exploring intrinsic capabilities that may influence our understanding of their biogeographic history. Results show that neotropical cichlids are relatively old in age and their diversity can be attributed to the age of the clade as opposed to an increase or decrease in rate of evolutionary diversification. For the northern Middle American herichthyin cichlids, a revised taxonomy of the group is offered based on robust taxonomic sampling and assessment of morphological characters to define genera. At a more exclusive taxonomic scale, phylogeographic structure is not observed for some lowland neotropical fishes in Middle America. Incorporation of physiological and behavioral data casts doubt on marine dispersal as the sole or primary mechanism of dispersal for these fishes. Overall results show the importance of an integrative approach to undertand the evolution and biogeography of freshwater fishes in the Neotropics

Clarification of type material for Bornean species of the genus Osteochilus (Cyprinidae)

Mcmahan, Caleb D., Mochel, Susan F. (2015): Clarification of type material for Bornean species of the genus Osteochilus (Cyprinidae). Zootaxa 4032 (1): 147-150, DOI: http://dx.doi.org/10.11646/zootaxa.4032.1.1

Peces Ciprinodontiformes de El Salvador

 Introduction: The Cyprinodontiformes are a group of secondary freshwater fishes widely distributed in El Salvador. Currently, many species of this group are usually incorrectly identified for lack of adequate tools. Additionally, their taxonomy and distribution have changed in recent years. Objective: To provide updated information about the taxonomy and distribution of El Salvador Cyprinodontiformes through identification keys, distribution notes, and general descriptions for all species. Methods: We carried out an extensive review of the literature, electronic databases, and museum specimens to generate a list of valid species present in El Salvador. Results: Eleven species in three families are confirmed: Profundulidae (two species), Anablepidae (one species), and Poeciliidae (eight species). We also include distribution data, both vertical and by main basins, and an illustrated guide. Conclusions: There are 11 species of Cyprinodontiformes in El Salvador and they can be found and identified with this article. Introducción: Los ciprinodontiformes son un grupo de peces secundarios de agua dulce ampliamente distribuidos en El Salvador. Actualmente hay errores de identificación por falta de herramientas adecuadas; además, su taxonomía y distribución han cambiado en los últimos años. Objetivo: Proporcionar información actualizada sobre la taxonomía y distribución de los Ciprinodontiformes de El Salvador a través de claves de identificación, notas de distribución y descripciones generales para todas las especies. Métodos: Realizamos una revisión extensa de la literatura, bases de datos electrónicas y especímenes de museo para generar una lista de especies válidas presentes en El Salvador. Resultados: Se confirman once especies en tres familias: Profundulidae (dos especies), Anablepidae (una especie) y Poeciliidae (ocho especies). También incluimos datos de distribución, tanto vertical como por cuencas principales, y una guía ilustrada. Conclusiones: Existen 11 especies de Cyprinodontiformes en El Salvador y se pueden encontrar e identificar con este artículo.&nbsp

Parascolopsis akatamae, a new species of dwarf monocle bream (Perciformes Nemipteridae) from the Indo-West Pacific, with redescription of closely related species P. eriomma

Miyamoto, Kei, Mcmahan, Caleb D., Kaneko, Atsushi (2020): Parascolopsis akatamae, a new species of dwarf monocle bream (Perciformes Nemipteridae) from the Indo-West Pacific, with redescription of closely related species P. eriomma. Zootaxa 4881 (1): 91-103, DOI: https://doi.org/10.11646/zootaxa.4881.1.