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Crenicichla yaha sp. n. (Perciformes: Labroidei: Cichlidae), a new species from the río Iguazú and arroyo Urugua-í basins, northeastern Argentina
... The genus Crenicichla Heckel is the most speciose lineage of Neotropical cichlids. In the present conception the genus includes about 80 valid species (Casciotta et al. 2006;Kullander & Lucena 2006;Kullander et al. in press) and this number is rapidly increasing (e.g., Casciotta et al. 2006;Kullander & Lucena 2006;Lucena 2007;Casciotta & Almirón 2008;Montaña et al. 2008;Kullander 2009). Stawikowski & Werner (2004) listed more than 120 known species including those yet undescribed. ...
... The genus Crenicichla Heckel is the most speciose lineage of Neotropical cichlids. In the present conception the genus includes about 80 valid species (Casciotta et al. 2006;Kullander & Lucena 2006;Kullander et al. in press) and this number is rapidly increasing (e.g., Casciotta et al. 2006;Kullander & Lucena 2006;Lucena 2007;Casciotta & Almirón 2008;Montaña et al. 2008;Kullander 2009). Stawikowski & Werner (2004) listed more than 120 known species including those yet undescribed. ...
... Recently there have been numerous discoveries of new fish species from Misiones (Miquelarena et al. 2002;Rodríguez & Miquelarena 2005;Casciotta et al. 2006;Casciotta & Almirón 2008), including so far two new species of Crenicichla, C. yaha and C. tesay. The aim of this paper is to describe another new species of Crenicichla from the arroyo Piray-Miní belonging to the Paraná basin. ...
A new species of Crenicichla Heckel, C. hu, is described from the arroyo Piray–Miní, a left-hand tributary of the río Paraná, Misiones province, Argentina. This new species is easily distinguished from its congeners in the La Plata basin and adjacent coastal rivers by the dark coloration (dark grey or dark brown to black), a color pattern consisting of 7 to 9 black irregular blotches on the flank, and 47–54 scales in the E1 row. Adult females have dorsal fin with an irregular color pattern formed by wide black and white longitudinal stripes and blotches. In addition to standard morphological comparisons, a brief molecular phylogenetic analysis of Crenicichla species from the province of Misiones is also introduced.
... PC1 and PC2 explain 47.26 % and 26.65 % of the total variation, respectively. Casciotta et al. (2006Casciotta et al. ( , 2010Casciotta et al. ( , 2013 and Piálek et al. (2010Piálek et al. ( , 2012 have documented that the lower/middle Paraná-Iguazú basins host a very diverse fauna of Crenicichla, comparable to the only known diversified Crenicichla fauna in the neighboring Uruguay river basin (Lucena and Kullander, 1992;Lucena, 2007;Piálek et al., 2012). Piálek et al. (2012) described the diversity of Crenicichla in the two neighboring river basins as a case of parallel evolution of two separate non-sister group clades of Crenicichla. ...
... The study of species diversity in complex groups such as the species complexes of Crenicichla pose a challenge to traditional taxonomy. Relying solely on scant morphological information from previously collected specimens without personal field information about their exact habitats, ecology, live coloration etc. can be misleading as shown in Casciotta et al. (2006Casciotta et al. ( , 2010Casciotta et al. ( , 2013, Casciotta and Almirón (2008), and Piálek et al. (2010Piálek et al. ( , 2012 in the case of description and confusion between C. yaha and C. tesay, or in Varella (2011) in case of C. sp. "IGUAÇU". ...
Five species of Crenicichla have been recorded so far from the lower Iguazú River. Four
of them are endemic (members of the C. mandelburgeri species complex from the C. lacustris group)
and living in sympatry; the fifth species (C. lepidota) belongs to an Amazon/Orinoco-centered species
group (C. saxatilis) and is only distantly related to the remaining species. The four sympatric species
differ substantially in their head/teeth morphology and related utilization of the ecological niches,
and represent all known ecomorphs within Crenicichla. Two of them, a gregarious small-mouthed
picker/grazer C. tapii sp. n. and a large-mouthed thick-lipped cavity explorer/excavator C. tuca sp. n.
are described here as new species. The piscivorous large-mouthed species C. iguassuensis represents
the ancestral form of the genus. The fourth species is the small-mouthed picker/molluscivore C.
tesay with a robust lower pharyngeal jaw with molariform teeth. Populations referred to in previous
studies as C. yaha are reclassified as C. tesay; C. yaha is an endemic species of the neighboring
Urugua-í stream known only from nine specimens because the species has not been collected since
1989 (when a dam was constructed on this stream). The taxonomic status of the populations referred
to here as C. iguassuensis remain tentative because these form a separate clade in mtDNA analysis,
reveal slight morphological differences, and have a wide distribution gap to the type locality with
similar yet undescribed species in the intervening area.
... Devido à grande importância em inventariar sua fauna de peixes, diversos pesquisadores isoladamente também vêm contrinbuindo nos últimos anos para o aumento no conhecimento da ictiofauna do Iguaçu. Neste contexto, podem ser destacados os trabalhos de Pinna (1992), Reis (1997), Wosiacki (1997), Lucinda e Garavello (2001), Almirón, Azpelicueta e Casciotta (2002), Azpelicueta, Casciotta e Almirón (2002, de Pinna e Wosiacki (2003), Vitule e Abilhoa (2003), Almirón, Azpelicueta e Casciotta (2004), Casciotta, Almirón e Azpelicueta (2004), Wosiacki e Garavello (2004), Garavello (2005), Haluch e Abilhoa (2005), Casciotta, Almirón e Gómez (2006aGómez ( , 2006b, Kullander e Ferreira (2006), Lucinda, Ghedotti e Graça (2006), Bifi, Baumgartner, Baumgartner, Frana e Debona (2006), Buitrago-Suárez e Burr (2007), Garavello e Shibatta (2007), Wosiacki e de Pinna (2007), Casciotta e Almirón (2008), Ingenito, Ghazzi, Duboc e Abilhoa (2008), Wosiacki e de Pinna (2008a, Alcaraz, Pavanelli e Bertaco (2009), Bifi, Pavanelli e Zawadzki (2009, Pavanelli e Bifi (2009), Pavanelli e Oliveira (2009) e Garavello e Sampaio (2010). ...
... iguassuenis, C. iguassuensis y a C. lacustris. A estas especies deben sumarse las recientemente descriptas Crenicichla yaha (Casciotta et al., 2006a) y C. tesay (Casciotta y Almirón, 2008). Las especies no se encuentran segregadas, aunque los juveniles y los adultos ocupan diferentes porciones del cauce, encontrándose los juveniles de hasta 15 cm cercanos a las orillas, mientras que los adultos se ubican en el centro, muchas veces en pozones profundos. ...
se realizaron intensas campañas de relevamiento íctico en el Alto Iguazú y algunos arroyos de la zona (Uruzú, Urugua-í), colectándose también muestras de agua desde Andresito y Yacutinga (25º33´S; 54º04´W) hasta Cataratas del Iguazú (25º31´S; 54º08´W). Nuestros datos químicos y observaciones biológicas indican escaso cambio en las condiciones en los últimos 20 años, salvo un aumento de la conductividad y la alcalinidad y disminución de la dureza. El río puede ser calificado como oligotrófico y oligohalino, de agua blanda, con baja numerosidad de especies, muchas de ellas endémicas. Durante las últimas campañas se registraron tres especies exóticas, posiblemente provenientes de represas brasileñas. La baja cantidad de especies y el alto número de endemismos se deben a la combinación de efectivas barreras zoogeográficas, al tamaño de la cuenca y a la oligotrofia del sistema. Los mayores riesgos para esta cuenca son el deterioro de la pluviselva subtropical, las alteraciones antrópicas del caudal, un posible proceso de salinización, la introducción de especies exóticas y la ampliación de la distribución de especies limítrofes. Rio iguazú superior: química del agua y comentarios biológicos sobre algunos de sus peces
... et al. 2005. More recently, at least 15 new species and records of the genera Crenicichla (Casciotta et al. 2006aLucena 2007;Casciotta & Almirón 2008;Piálek et al. 2010), Australoheros (Casciotta et al. 2006b;Říčan & Kullander 2008;Říčan et al. 2011), Hoplias (Oyakawa & Mattox 2009), Rhamdella (Bockmann & Miquelarena 2008), Hisonotus (Azpelicueta et al. 2007), Pimelodus (Almirón et al. 2009), Cnesterodon (Aguilera et al. 2009) andRineloricaria (Rodriguez & were reported for this province. Nevertheless, many low order mountain streams, including the Ramos stream, are still unexplored. ...
The fish fauna of a subtropical mountain stream in Argentina was surveyed for the first time. The abundance and occurrence of species were explored considering variation in hydrology, seasonality and the abiotic environment. We collected 221 individuals of 23 species from 10 families and four orders. Small sized species and small individuals dominated the fish fauna. The small characid Astyanax saguazu was the most conspicuous species. Hydrology, seasonal changes in water temperature and variation in water conductivity affected the abundance and distribution of fish. Hypobrycon maromba is recorded in Argentina for the first time.
The Crenicichla mandelburgeri species complex from the Middle Paraná shows parallel evolution of ecomorphs to the unrelated Crenicichla missioneira species complex from the Uruguay River. In this article, we describe a new species pair (C. sp. Piray Guazú and C. sp. Piray Guazú Line) from the C. mandelburgeri species complex that has evolved a parallel morphological and ecological dichotomy to another species pair from the same species complex (Crenicichla ypo, Crenicichla yjhui) and also to species in the unrelated C. missioneira species complex (C. missioneira, Crenicichla celidochilus). The new species pair is endemic to a single tributary (the Piray Guazú) of the Middle Paraná River where it is sympatric and partly syntopic. Mitochondrial DNA phylogeny shows the two new species as distantly related within the C. mandelburgeri species complex, each with a sister species in the Iguazú rather than in the neighbouring Paraná river tributaries. Reduced genome representation ddRAD analyses of the nuclear genome demonstrate their close relationship, which is however complicated by the hybrid origin of one of the new species (C. sp. Piray Guazú Line). The hybrid origin of this species is demonstrated by sharing the ancestral genetic stock with its sympatric sister species (C. sp. Piray Guazú) while having an admixture from the widespread species C. mandelburgeri from the main Middle Paraná channel. In this study we also review the role of biogeography and mitonuclear discordance during evolution of the whole C. mandelburgeri species complex.
Crenicichla is the largest and most widely distributed genus of Neotropical cichlids. Here, we analyze a mtDNA dataset comprising 681 specimens (including Teleocichla, a putative ingroup of Crenicichla) and 77 out of 105 presently recognized valid species (plus 10 out of 36 nominal synonyms plus over 50 putatively new species) from 129 locations in 31 major river drainages throughout the whole distribution of the genus in South America. Based on these data we make an inventory of diversity and highlight taxa and biogeographic areas worthy of further sampling effort and conservation protection. Using three methods of molecular species delimitation, we find between 126 and 168 species-like clusters, i.e., an average increase of species diversity of 65-121% with a range of increase between species groups. The increase ranges from 0% in the Missioneira and Macrophthama groups, through 25-40% (Lacustris group), 50-87% (Reticulata group, Teleocichla), 68-168% (Saxatilis group), 125-200% (Wallacii group), and 158-241% in the Lugubris group. We found a high degree of congruence between clusters derived from the three used methods of species delimitation. Overall, our results recognize substantially underestimated diversity in Crenicichla including Teleocichla. Most of the newly delimited putative species are from the Amazon-Orinoco-Guiana (AOG) core area (Greater Amazonia) of the Neotropical region, especially from the Brazilian and Guiana shield areas of which the former is under the largest threat and largest degree of environmental degradation of all the Amazon.
We address the diversity of two species
groups of the cichlid genus Gymnogeophagus in the
Middle Paraná basin using molecular phylogeography
and traditional morphological characters and conclude
that they are composed of a higher diversity of
endemic species than previously thought. The nominal
Gymnogeophagus setequedas is found non-monophyletic with each phylogeographic lineage endemic
to a single tributary of the Middle Paraná (Rio Acaray,
Rio Monday, the Itaipu area). Prime candidates for the
origin of the species in the G. setequedas group are
waterfalls that separate most of the tributaries from the
Middle Paraná River. The postulated waterfall- and
rapids-driven fragmentation of Gymnogeophagus in
the studied area falls into a narrow time window
coinciding with the Pleistocene epoch. We further
demonstrate that the endemism in Gymnogeophagus
shows a high degree of biogeographical congruence
with other sympatric cichlid genera. The Middle
Paraná basin has up to 27 globaly endemic species of
cichlid fishes in three genera and 21 of these species
are endemics of single tributaries of the Middle
Paraná. As a final consideration we address threats to
the long term survival of the still poorly known but
clearly highly endemic and endangered fish fauna of
the Middle Paraná basin. PDF full text link: https://rdcu.be/3faF
Crenicichla lucenai sp. n. from the upper Rio das Antas basin, dos Patos lagoon system, southern Brazil is here described. The new species is similar to C. punctata and C. maculata. It is distinguished from both these species by the conspicuous pattern of dark brown irregular lines extending from longitudinal stripe to ventral profile (versus irregular lines absent). In addition, C. lucenai can be distinguished from C. punctata by the absence of dots on the sides of its head.
Crenicichla tesay, a new species of cichlid (Perciformes: Labroidei) from the río Iguazú basin in Argentina. - Crenicichla tesay sp. n. differs from its congeners by the following combination of characters: posterior border of preopercle serrated, 48-59 scales on El row, snout length 2.6-2.8 times in head length, presence of conspicuous suborbital stripe, flanks with 4 to 6 blotches below the upper lateral line, posteriormost blotch extending on caudal peduncle. Colour pattern with numerous irregularly scattered dots, and absence of vertical stripes on flanks.
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