Mayaweckelia troglomorpha, a new subterranean amphipod species from Yucatán state, México (Amphipoda, Hadziidae)

Abstract

A detailed description of a new stygobiont species of the amphipod family Hadziidae, Mayaweckelia troglomorpha Angyal, sp. n. is given, based on material collected in four cenotes of Yucatán federal state, México. Morphology was studied under light microscopy and with scanning electron microscopy. Morphological description is complemented with mitochondrial cytochrome c oxidase subunit I (COI) sequences as barcodes, with affinities to the related taxa and with notes on the species’ ecology. Using COI Bayesian inference and genetic distance analyses, we show that the closest relative of the new species is M. cenoticola, forming a monophyletic group referring to the genus Mayaweckelia. Based on the available sequences, we also revealed that Mayaweckelia and Tuluweckelia are sister genera, standing close to the third Yucatán subterranean genus, Bahadzia. The data gathered on the habitat, distribution, abundance, and ecology will contribute to the conservation planning for M. troglomorpha Angyal, sp. n.

New distribution records of subterranean crustaceans from cenotes in Yucatan (Mexico)

“…Prior to this study, the amphipod T. cernua was only known from Quintana Roo, mostly associated with saltwater habitats in anchialine cenotes near the northeastern coastline of the Peninsula (Holsinger 1990;Rocha et al 1998;Álvarez and Iliffe 2008;Álvarez et al 2015). Contrary to previous findings, all individuals were found in freshwater habitats during our study (Angyal et al 2018). Rocha et al (1998) and Pesce and Iliffe (2002) mentioned observation records of 'thermosbaenaceans' from cenotes Yuncu, Mucuyche, Pabakal (Papakal), and Grutas de Tzab-Nah (all in Yucatan).…”

“…The present study confirms first records for T. cernua and T. unidens in the state of Yucatan. Together with the amphipod M. troglomorpha, which was discovered and described within the frame of herein presented expeditions (Angyal et al 2018) and the new cave isopod Curassanthura yucatanensis Álvarez, Benítez, Iliffe & Villalobos, 2019(Álvarez et al 2019, the list of stygobiotic crustaceans recorded for the state of Yucatan raised from 22 (in 2016) to 26. In addition, the cirolanid isopod C. yunca was only known from its type locality, but we now provide distribution data for this species in three other localities.…”

“…As M. troglomorpha was found in approximately 30% of the visited sites, it does not appear to be a rare freshwater stygobiotic element in the Yucatan cenotes. Holsinger 1977Holsinger , 1990Reddell 1981;Álvarez and Iliffe 2008, Álvarez et al 2015, Angyal et al 2018, Benítez et al 2019 Type locality is Cenote Xtacabiha (Yucatan). From Yucatan the species was also known from Cueva de Orizaba, Cenote Nohchen, Grutas de Tzab-Nah and Grutas de Santa Maria.…”

“…The dissections were then mounted on slides and examined using a Leica DM 1000 compound light microscope (Fišer et al 2009;Angyal et al 2015). For the identification of the collected material the following publications were used: Álvarez et al 2005;Álvarez and Iliffe 2008;Angyal et al 2018;Botosaneanu and Iliffe 1999Bowman 1966Bowman , 1977Bruce 1986;Creaser 1936;Hobbs and Hobbs 1976;Hobbs et al 1977;Hobbs 1979;Holsinger 1977Holsinger , 1990Horwitz et al 1995;Kallmeyer and Carpenter 1996;Lowry and Myers 2013;Meland et al 2015;Pérez-Aranda 1983a, 1983b, 1984a, 1984bTinnizi and Quddusi 1993;Wagner 1994. Photographs were made using an OMAX 14 OMP digital USB microscope camera, a Nikon D5300, and a Nikon D7000 with 60 mm macro lens.…”

“…Intrusion of saline water is found deeper as the distance from the coastline increases (Bauer-Gottwein et al 2011). Therefore, most inland cenotes within the state of Yucatan are exclusively freshwater systems, except for a few rather deep ones with haloclines below 50 m in depth, and those located near the northern coastline of the Peninsula (Álvarez et al 2005;Angyal et al 2018).…”