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Stiassny M.L.J.,American Museum of Natural History | De Marchi G.,Museo Civico di Storia Naturale di Milan | Lamboj A.,University of Vienna
Zootaxa | Year: 2010

A new species of cichlid fish is described from a small, endorheic lake (Lake Abaeded), situated some 30 m below sea level in the Danakil Depression of Eritrea (East Africa). Danakilia dinicolai is readily distinguished from its congener, D. franchettii, on the basis of body proportions and in the possession of markedly longer pectoral fins at all sizes. Additionally, oral dentition is more robust than that of its congener, and the lower pharyngeal jaw is markedly hypertrophied and covered with considerably finer and more densely implanted teeth on the posterior field of the jaw. Copyright © 2010.

Marchi G.D.,University of Pavia | Fasola M.,University of Pavia | Chiozzi G.,Museo Civico di Storia Naturale di Milan | Bellati A.,University of Pavia | Galeotti P.,University of Pavia
Waterbirds | Year: 2012

Determining the sex of Crab Plovers (Dromas ardeola) based on morphology has, hitherto, proven difficult. Here, six morphological traits (head-bill length, bill length, bill depth, wing chord, tarsus length and weight) of 39 molecularly or behaviorally sexed breeding Crab Plovers were compared in order to find a reliable morphometric way to determine their sex. Males were significantly larger than females in all traits, except tarsus length, and especially in traits related to head and bill size, where males were 6.8 to 11.4% larger than females. Discriminant Function Analysis correctly classified 97.4% of birds using only bill depth and bill length, providing an efficient tool for sexing Crab Plovers in the hand.

Hamdan B.,Federal University of Rio de Janeiro | Hamdan B.,Colecao Cientifica Instituto Vital Brazil | Scali S.,Museo Civico di Storia Naturale di Milan | Fernandes D.S.,Federal University of Rio de Janeiro
Zootaxa | Year: 2014

The snake genus Chironius Fitzinger, 1826 is endemic to the Neotropical region, occurring from Honduras to Uruguay and northeastern Argentina. Some species of the genus have taxonomic and/or nomenclatural problems, such as C. flavo-lineatus which lacks agreement in the literature about its authorship and type locality. Some researchers have been sug-gesting Jan (1863) as the author of the species since he first described C. flavolineatus based on two specimens. However, other researchers report that Jan's description is so incomplete that it is not possible to ascertain what snake he had in mind and therefore suggest Boettger (1885) as the author, since he was the first to provide a detailed description of the species. In the present study one of the syntypes of C. flavolineatus, supposedly destroyed in Second World War, was found. Thus, the taxonomic identity of C. flavolineatus was redefined, its lectotype was designated and the authorship of the taxa is attributed to Jan (1863). Copyright © 2014 Magnolia Press.

Curcio F.F.,Federal University of Mato Grosso | Scali S.,Museo Civico di Storia Naturale di Milan | Rodrigues M.T.,University of Sao Paulo
Herpetological Monographs | Year: 2015

We reassessed the taxonomic status of the xenodontine snake Erythrolamprus bizona Jan (1863) based on a comprehensive review of literature records and comparative material. Our data demonstrate that the original diagnosis does not allow the unambiguous attribution of the name E. bizona to any population of the genus. After a thorough investigation in European institutions, we recovered two syntypes of the E. bizona type-series, confirming its composite nature. To circumvent the problem, we herein designate a lectotype for the species, providing a reformulated diagnosis and a detailed redescription. The lectotype represents one of the rare remaining specimens used in Giorgio Jan's original descriptions during the second half of 19th century, and is housed in the Museo Civico di Storia Naturale di Milano, Milan, Italy. For more than seven decades, herpetologists have assumed that such material had been lost forever due to bombings of World War II. Nonetheless, our finding corroborates recent studies demonstrating that at least some of Jan's snake types still exist for taxonomic research. Finally, we discuss the geographic congruence of the frequency distributions of segmental counts under an integrative approach aiming to maintain nomenclatural stability without ignoring preliminary evidence of taxonomic diversity. © 2015 by The Herpetologists' League, Inc.

Ficetola G.F.,University of Milan Bicocca | Bonardi A.,University of Milan Bicocca | Colleoni E.,University of Milan Bicocca | Padoa-Schioppa E.,University of Milan Bicocca | Scali S.,Museo Civico di Storia Naturale di Milan
Evolutionary Biology | Year: 2013

The evolution of sexual dimorphism is an important topic of evolutionary biology, but few studies have investigated the determinants of sexual dimorphism over broad phylogenetic scales. The number of vertebrae is a discrete character influencing multiple traits of individuals, and is particularly suitable to analyze processes determining morphological variation. We evaluated the support of multiple hypotheses concerning evolutionary processes that may cause sexual dimorphism in the number of caudal vertebrae in Urodela (tailed amphibians). We obtained counts of caudal vertebrae from >2,000 individuals representing 27 species of salamanders and newts from Europe and the Near East, and integrated these data with a molecular phylogeny and multiple information on species natural history. Per each species, we estimated sexual dimorphism in caudal vertebrae number. We then used phylogenetic least squares to relate this sexual dimorphism to natural history features (courtship complexity, body size dimorphism, sexual ornamentation, aquatic phenology) representing alternative hypotheses on processes that may explain sexual dimorphism. In 18 % of species, males had significantly more caudal vertebrae than females, while in no species did females have significantly more caudal vertebrae. Dimorphism was highest in species where males have more complex courtship behaviours, while the support of other candidate mechanisms was weak. In many species, males use the tail during courtship displays, and sexual selection probably favours tails with more vertebrae. Dimorphism for the number of tail vertebrae was unrelated to other forms of dimorphism, such as sexual ornamentation or body size differences. Multiple sexually dimorphic features may evolve independently because of the interplay between sexual selection, fecundity and natural selection. © 2012 Springer Science+Business Media New York.

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