Morphological abnormality in a Longnose Stingray Hypanus guttatus (Bloch & Schneider, 1801) (Myliobatiformes: Dasyatidae)

Abstract

A Longnose stingray Hypanus guttatus (Bloch & Schneider, 1801) embryo with a major asymmetrical morphological abnormality to its pectoral fin was obtained from commercial shrimp fisher's bycatch, off the coast of the Amazon River Mouth in northern Brazil. The specimen and the deformity, which would presumably have impeded its long-term survival, are described and documented in detail. We herein provide the first report of an abnormal individual of this species for the Brazilian coast.Resumo: Um embrião de Arraia-bicuda Hypanus guttatus (Bloch & Schneider, 1801) com uma anomalia morfológica assimétrica grave na nadadeira peitoral foi obtido como captura-acidental de um barco de pesca de camarão da costa da foz do rio Amazonas, no norte do Brasil. O indivíduo e sua deformação, que provavelmente teria impedido sua sobrevivência ao longo prazo, são descritos e documentados em detalhe. Apresentamos com esse estudo o primeiro registro de um indivíduo anormal dessa espécie para a costa do Brasil.

Morphological abnormalities in the Chilean Eagle ray Myliobatis chilensis (Myliobatiformes: Myliobatidae) off the Peruvian coast, Southeast Pacific

“…The three cases of morphological abnormalities reported here could be the result of di昀昀erent factors such as genetics (Ramírez-Hernandez et al, 2011;Ball et al, 2013;Bhagyalekshmi and Kumar, 2019), parasitism (Heupel et al, 1999;Bejarano-Álvarez and Galván-Magaña, 2013;Bhagyalekshmi and Kumar, 2019;Schmid et al, 2019), marine pollution or non-favorable environmental parameters (Mnsari et al, 2010;Bukola et al, 2015;Jawad et al, 2018). The transformation of the desertic coast of the Libertad region into enormous agro-industrial plots by the Chavimochic irrigation project resulted in contamination by nitrogenic compounds and phosphates from agricultural residues (Bukola et al, 2015), such as fertilizers and pesticides and likely led to embryo malformations and neoplastic processes (Austin, 1999).…”

Living naked: first case of lack of skin‐related structures in an elasmobranch, the blackmouth catshark (Galeus melastomus)

“…The most reported congenital morphological abnormalities in elasmobranchs regard skin colour aberrations, reproductive system and skeleton. Skeletal malformations are usually more severe and, thus, mainly observed among embryos (Moore, 2015), as they include alterations in the axial skeleton, in the cranium and in the development of fins ( e.g ., Afonso et al ., 2016; Escobar‐Sánchez et al ., 2014; Heupel et al ., 1999; Lamarca et al ., 2017; Mancini et al ., 2006; Moore, 2015; Sans‐Coma et al ., 2017; Schmid et al ., 2019). Skin colour aberrations, as well as reproductive system abnormalities, usually represent less severe conditions and are recorded to a greater extent among adult, free‐swimming individuals (Moore, 2015).…”