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Morphological and Genetic Comparisons of Golden Crayfish, Orconectes luteus, and Rusty Crayfish, O. rusticus, with range corrections in Iowa and Minnesota

Journal of Crustacean Biology (Impact Factor: 1.19). 05/2004; 24(4):603-617. DOI: 10.1651/C-2483

ABSTRACT The distribution of the rusty crayfish, Orconectes rusticus, has been purported to include large portions of Iowa and Minnesota among many other states, whereas the golden crayfish, O. luteus, has been reported from Kansas, Arkansas, Missouri, and Illinois. Recent collections made in several river basins in Iowa and southern Minnesota and examination of museum specimens collected in Iowa revealed that many records attributed to O. rusticus are in fact O. luteus. We provide a suite of quantitative and qualitative characteristics, both morphological and genetic, that distinguish O. luteus and O. rusticus and also demonstrate that female O. luteus exhibit form alternation. Comparisons of mitochondrial 16S rRNA haplotypes among populations of O. luteus, O. rusticus, O. cf. rusticus, O. placidus, and O. virilis revealed relatively high levels of sequence divergence among taxa as well as within some taxa. We conclude that O. luteus is a native species in Iowa and southern Minnesota with introduced populations of O. rusticus occurring in both states. A more thorough survey of these states, particularly Iowa, is needed to assess the distributions of O. rusticus and O. luteus. If O. rusticus has a relatively restricted distribution in Iowa, efforts to control its anthropogenic and natural dispersal may be more effective if implemented in the near future. Our study indicates the need for more research in taxonomy, even in regions where the fauna is thought to be known well, in order for the conservation of native species and detection and management of nonindigenous species to be successful.

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    • "). The structure of the first pleopods is consistent with the definition of the subgenus Procericambarus within the genus Orconectes; however, molecular data do not support that the subgenus is monophyletic as defined currently (Fetzner 1996, Crandall and Fitzpatrick 1996, Wetzel et al. 2004 "
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    ABSTRACT: A new crayfish is described from the main channel of the lower Ohio River between Illinois and Kentucky based on examination of over 185 specimens. The new species, with gonopods of form I males typical of the subgenus Procericambarus (sensu Fitzpatrick), accounts for some of the variation previously ascribed to Orconectes placidus in Illinois. O. pardalotus is most similar to allopatric O. forceps, O. barrenensis, and O. durelli but can be distinguished from them and other species using colour in life, shape of chelae, and other characters. Colour in life can be used to diagnose O. pardalotus, and preserved specimens can be distin-guished from sympatric O. placidus and many other species by the shape of the chelae and the absence of a distomedian carpal spine on the first pereiopod of O. pardalotus (present in O. placidus) and can be distin-guished further from O. luteus using denticle arrange-ment on the chelae and structure of the gonopods of form I males. O. pardalotus is associated with rocky microhabitats at and below the summer minimum water level of the Ohio River. Notes about reproductive period and oviposition of captive specimens are provided. Zusammenfassung Beschrieben wird eine neue Flusskrebsart vom Hauptarm des unteren Ohio River zwischen Illinois und Kentucky auf der Grundlage von über 185 Exemplaren. Die Merkmale der Gonopoden bei männlichen Exem-plaren (Form I) der neuen Art, wie sie für die Untergat-tung Procericambarus (sensu Fitzpatrick) typisch sind, entsprechen teils den Variationen, die früher Orconectes placidus in Illinois zugeordnet wurden. Am meisten ähnelt O. pardalotus den allopatrischen For-men O. forceps, O. barrenensis und O. durelli, doch lässt sich die neue Art durch Lebendfärbung, Form der Scheren und weitere Merkmale unterscheiden. Die Lebendfärbung eignet sich zur raschen Bestimmung von O. pardalotus, während bei konservierten Exem-plaren die Unterscheidung zur sympatrischen Art O. placidus und vielen anderen Arten durch die Gestalt der Scheren möglich ist; außerdem fehlt bei O. pardalotus am ersten Pereiopod der distomediane Carpalstachel (bei O. placidus vorhanden); zur Unterscheidung von O. luteus dienen die Anordnung der Zähnchen an den Scheren und die Struktur der Gonopoden bei Män-nchen (Form I). Lebensraum von O. pardalotus bilden felsige Mikrohabitate unterhalb des sommerlichen Niedrigwasserspiegels im Ohio. Angefügt sind einige Bemerkungen zur Fortpflanzungszeit und Eiablage nach Beobachtungen an gefangenen Exemplaren. Résumé Est décrite une nouvelle Ecrevisse du cours principal du bas Ohio River, entre l'Illinois et le Kentucky, sur base de l'examen de plus de 185 spécimens. La nou-velle espèce, avec de gonopodes de la forme I des mâles typiques pour les sous-genre Procericambarus (sensu Fitzpatrick), rend compte de la variation autre-fois attribuée à Orconectes placidus de l'Illinois. O. pardalotus se rapproche le plus des allopatriques O. forceps, O. barrenensis et O. durelli, mais se distingue d'elles et d'autres espèces par la couleur in vivo, la forme de la chéla et d'autres caractéristiques. La couleur in vivo peut servir à diagnostiquer O. pardalo-tus et les spécimens conservés peuvent se distinguer de l'O. placidus sympatrique et de beaucout d'autres espèces par la forme de la chéla et l'absence d'une épine carpienne distomédiane sur le premiere péréiopode d'O. pardalotus (présente chez O. placidus) et peut être distinguée ensuite d'O. luteus par l'agencement des denticules sur la chéla et par la structure des gonopodes de mâles de forme I. O. pardalotus est inféodé aux microhabitats rocheux, à hauteur de et sous le niveau minimum estival de l'Ohio River. Des données sont fournies sur la période de reproduction et sur le positionnement des oeufs pour des spécimens en captivité. Sommario Una nuova specie di gambero è descritta dal canale principale del fiume Ohio inferiore tra l'Illinois e il Ken-tucky sull'esame di oltre 185 esemplari. La nuova specie, con gonopodi maschili di forma I tipici del genere Procericambarus (sensu Fitzpatrick), raccoglie alcune delle variazioni precedentemente descritte per Orconectes placidus dell'Illinois. Orconectes pardalo-tus è più simile alle specie allopatriche O. forceps, O. barrenensis, e O. durelli, ma può essere distinta da esse e da altre specie sulla base del colore in vita, della forma delle chele e di altri caratteri. La colorazione può essere usata per diagnosticare O. pardalotus e gli esemplari conservati possono essere distinti dalla specie simpatrica O. placidus e da molte altre specie per la forma delle chele e per l'assenza di una spina carpale distomediana sul primo pereiopode di O. pardalotus (presente in O. placidus) e può essere dis-tinta ulteriormente da O. luteus utilizzando la dispo-sizione dei dentelli sulle chele e la struttura dei gonopodi maschili di forma I. Orconectes pardalotus è associato a microhabitat rocciosi a livello o al di sotto del limite idrometrico estivo minimo del fiume Ohio. Vengono fornite alcune note sul periodo riproduttivo e la deposizione delle uova in specie in cattività.
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    ABSTRACT: Two species of cambarids have been reported for the Yucatan Peninsula, Procambarus llamasi and P. pilosimanus, the latter with a distribution that stretches from the south of Veracruz to the south of Campeche. However, during the last decade only the presence of P. llamasi has been reported; as a consequence, and also because of the biogeographic isolation of the Laguna de Chichancanab, we here investigated two southern populations, Procambarus sp. from Laguna de Chichancanab, Quintana Roo (LCh) and Procambarus llamasi from Ignacio Zaragoza, Campeche (IZa). We investigated these at the molecular level in order to determine if they are independent genetic units. The levels of genetic heterogeneity of the mitochondrial r16S and subunit I of the cytochrome oxidase (CO-I) genes are thus evaluated and contrasted to the levels of the cambarellinid, Cambarellus montezumae from the Xochimilco Channels, D. F. (XCh). The phylogenetic relations of these populations in relation to other Neartic and Neotropical astacoids (Astacidae and Cambaridae) and Caribbean atyids (Atyidae) were investigated. Levels of genetic diversity (h and π) in both r16S and CO-I were lower in the southeastern populations in relation to the Cambarellinae from central Mexico. For instance, π ranged from 0.00000 to 0.00149 for r16S and CO-I, respectively, in the southeastern populations, whereas the central population showed levels that ranged from 0.00250 to 0.00232 for the same gene regions. Both gene regions indicate significant levels of structuring among the southeastern populations (F ST , 0.714 and 0.612, P < 0.0001, for r16S and CO-I), and these results are supported by the lack of actual gene flow. However, in order to confirm this hypothesis a larger number of populations along the range of distribution of the species should be tested. The phylogenetic reconstruction by maximum parsimony (MP), minimum evolution (ME), and maximum likelihood (ML) of these populations and other astacids and atyids, confirms the monophyly of the two southeastern populations (P. llamasi) as well as of C. montezumae, and suggests that Cambaridae constitutes a non-monophyletic assemblage, a hypothesis herein confirmed by a total evidence Bayesian analysis. Se han reportado dos especies de cambáridos para la Península de Yucatán, Procambarus llamasi y P. pilosimanus, éste ultimo con una distribución que va del sur de Veracruz al sur de Campeche. Sin embargo, durante la última década solo se ha registrado la presencia de P. llamasi. Además y debido al aislamiento de la Laguna de Chichancanab, en el presente trabajo se investigan a nivel molecular a dos poblaciones sureñas, Procambarus sp. de la Laguna de Chichancanab, Quintana Roo (LCh) y Procambarus llamasi de Ignacio Zaragoza, Campeche (IZa), para determinar sí son unidades genéticas independientes. Se evalúan y contrastan los niveles de heterogeneidad de las subunidades mitocondriales r16S y citocromo oxidasa I (CO-I) con relación a las del cambarelinido Cambarellus montezumae de los Canales de Xochimilco, D.F. (XCh). Se investigan las relaciones filogenéticas de éstas poblaciones en relación a especies de astacoideos Neárticos y Neotropicales (Astacidae y Cambaridae) y de atyidos caribeños (Atyidae). Los niveles de diversidad genética (h and π) para r16S y CO-I fueron más bajas en las poblaciones sureñas en relación al cambarelinido del centro de México. Por ejemplo, π varió de 0,00000 a 0,00149 para r16S y CO-I, respectivamente, para las poblaciones sureñas, mientras que para la población central los valores variaron entre 0,00250 y 0,00232 para las mismas regiones. Ambas regiones génicas mostraron niveles significativos de estructuración entre las poblaciones sureñas (F ST , 0,714 y 0,612, P < 0,0001, para r16S y CO-I), resultados que son apoyados por los bajos niveles de flujo génico, sin embargo un mayor número de poblaciones a lo largo de la distributión de la especie deberán ser muestreadas para corroborar dicha hipótesis. La reconstructión fllogenética de estas poblaciones y otros astacoideos y atyidos y por medio de máxima parsimonia (MP), mínima evolutión (ME) y máxima verosimilitud (ML) confirman la monofilia de las dos poblaciones sureñas (P. llamasi), así como la de C. montezumae y sugieren que la familia Cambaridae es un ensamble no-monofilético, hipótesis que se conflrma con un análisis Bayesiano de evidencia total.
    Crustaceana 08/2010; 83(9):1035-1053. DOI:10.2307/41038614 · 0.47 Impact Factor
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    Journal of Crustacean Biology 11/2012; 32(6):962-971. DOI:10.1163/1937240X-00002091 · 1.19 Impact Factor