Karyotype analysis of three species of Corydoras (Siluriformes: Callichthyidae) from southern Brazil: rearranged karyotypes and cytotaxonomy

The genus Corydoras comprises a diversity of species with different diploid numbers. We compared cytogenetic data among Corydoras species from different rivers of the Ponta Grossa Arch region in southern Brazil. Corydoras ehrhardti and C. aff. paleatus have a similar karyotype formula and the same diploid number (2n = 44). Corydoras lacrimostigmata has a higher diploid number, with 2n = 58 chromosomes. Fluorescence in situ hybridization using 5S and 18S ribosomal DNA probes suggests that these ribosomal DNA sequences are involved in chromosomal rearrangements in these Corydoras species. 5S rDNA is a chromosomal marker that is considered to be unique to the species analyzed in this study. Signals of interstitial telomeric sites are seen in a chromosome pair of C. lacrimostigmata, suggesting chromosomal rearrangements via fusions or translocations. This study revealed that C. ehrhardti and C. aff. paleatus have exclusive chromosomal markers associated with chromosome differentiation, which we speculate to prevent genetic introgression.(AU)

Corydoras compreende um gênero diversificado com espécies de diferentes números diploides. Nós comparamos dados citogenéticos de espécies de Corydoras de diferentes rios da região do Arco de Ponta Grossa no sul do Brasil. Corydoras ehrhardti e C. aff. paleatus tem fórmula cariotípica similar e o mesmo número diploide (2n = 44). Corydoras lacrimostigmata tem um número diploide maior, com 2n= 58 cromossomos. A hibridação in situ fluorescente (FISH) com sondas de DNA ribossomal 5S e 18S sugere que estas sequências de DNA ribossomal estão envolvidas em rearranjos cromossômicos nestas espécies de Corydoras. A marcação do DNAr 5S foi considerada espécie-específico para as espécies analisadas neste estudo. Sinais de sítios teloméricos intersticiais foram vistos em um par de cromossomos de C. lacrimostigmata sugerindo a ocorrência de rearranjos cromossômicos como fusões ou translocações. Este estudo revelou que as espécies C. ehrhardti e C. aff. paleatus têm marcadores cromossômicos exclusivos associados à diferenciação cromossômica, os quais, em nossa hipótese, podem prevenir a introgressão gênica.(AU)

Una nueva subespecie de Heraclides androgeus (Lepidoptera: Papilionidae) y sus aspectos biogeográficos / A new subspecies of Heraclides androgeus (Lepidoptera: Papilionidae) and its biogeographical aspects

Heraclides androgeus epidaurus was described and illustrated by Godman & Salvin in 1890 based on specimens obtained in Veracruz, indicating that their distribution encompassed both the Pacific and Atlantic sides of Mexico. Later authors commented that there were morphological differences between the male wings from both populations. We analyzed, described and nominated Heraclides androgeus reyesorum ssp. nov. Vargas, Llorente & Luis distributed in the Mexican Pacific coast, based on 62 specimens, and compared it with H. a. epidaurus from the Gulf of Mexico, based on more than 200 specimens housed at UNAM: Museo de Zoología, Facultad de Ciencias and the Colección Nacional de Insectos of the Instituto de Biología, as well as some collections from the USA. The main characters were the width of the yellow and black bands on forewings in males, which had a significant difference between the populations of both sides of Mexico, although some characters were variable and showed partial overlap. In the hindwings, the differences were the extent of the subterminal lunules in dorsal and ventral view. We also analyzed the male genitalia, finding notorious differences in both sclerotic processes of the harpe. Subspecific differences between females refer to the brightness and extent of green spots on the hindwings and the extent of lunules in the ventral view. The greatest abundance of H. a. reyesorum ssp. nov. was in the tropical deciduous forest, with gallery forest and in the lower range of the cloud forest, present at altitudes of 500-800m and 1 000-1 750m, respectively. We discussed the pattern of endemism due to historical vicariant processes and explain the presence of the new subspecies of H. androgeus and other taxa of specific level.

Hemos reunido evidencia de que Heraclides está formado por dos subespecies, cada una con caracteres propios que las distinguen; analizamos, describimos y nominamos a Heraclides androgeus reyesorum ssp. nov. que se distribuye en la costa pacífica mexicana. Los principales caracteres masculinos fueron la amplitud de las bandas amarilla y negra en alas anteriores, que al cuantificarse y analizarse tuvieron una diferencia significativa entre las poblaciones de las dos vertientes de México, a pesar que algunos caracteres son variables y muestran superposición parcial. En alas posteriores las diferencias fueron la amplitud de lúnulas subterminales en vista dorsal y ventral. Se analizaron los genitales masculinos, se encontraron diferencias determinantes en los procesos esclerosados del harpagón. Las diferencias subespecíficas entre hembras se refieren al brillo y extensión de las manchas verdes en alas posteriores y a la amplitud de lúnulas en vista ventral. La mayor abundancia de H. a. reyesorum ssp. nov. fue en el bosque de galería del bosque tropical caducifolio y en el intervalo inferior del bosque mesófilo, a 500-800m y 1 000-1 750m, respectivamente. Se discute la existencia de un patrón de endemismo analizado por Halffter (1978) y Morrone & Llorente (2006) que obedece a procesos históricos vicariantes y resume la presencia de subespecies nuevas en el Pacífico como en H. androgeus y muchos otros taxones.