Resurrection of Pilumnus vinaceus A. Milne-Edwards, 1880 (Brachyura: Pilumnidae) using integrative evidence from molecular and morphology

Abstract

The hairy crab Pilumnus vinaceus A. Milne-Edwards, 1880, previously considered to be a junior synonym of Pilumnus dasypodus Kingsley, 1879 by Rathbun (1897) is here resurrected. Pilumnus vinaceus can be distinguished from the known western Atlantic species (including P. dasypodus) based on morphological characters and molecular markers. This action increases number of reported species of Pilumnus in the western Atlantic to nineteen.

A description of the first zoeal stage of Pilumnus vinaceus A. Milne-Edwards, 1880 (Decapoda, Pilumnidae), with a revision of the first zoea morphology of Pilumnus Leach, 1815

“…In the laboratory, the specimens were identified following a set of diagnostic characteristics (Melo, 1996;Magalhães et al, 2021). Each ovigerous females were maintained in the aquarium facilities of both Laboratory of Biology of Marine and Freshwater Shrimp (LABCAM), at São Paulo State University (UNESP), campus of Bauru and Laboratory of Bioecology and Systematic (LBSC), at University of São Paulo (USP), campus of Ribeirão Preto (FFCLRP), until the larvae hatch.…”

“…Pilumnus Leach, 1815 comprises about 150 species (Ng et al, 2008;Magalhães et al, 2021), popularly known as "hairy crabs" because they have many setae distributed over the carapace and/or pereiopods. These crabs are common in many coastal environments (e.g., coral reefs [Garth, 1984;Giraldes et al, 2015], rocky shores [Kyomo, 1999;Alves et al, 2012;Moraes et al, 2015], unconsolidated bottom [Melo et al, 2000;Ng, 2000] and in association with invertebrates [Lindberg & Frydenborg, 1980;Alves et al, 2012b;Alves et al, 2013]), mainly in tropical regions, but also in temperate zones (Takeda & Miyake, 1969;Williams, 1984;Melo, 1996).…”

“…Despite the current stability in terms of the phylogenetic position of this genus, the taxonomy and systematics of the assigned species are still unsatisfactory (Guerao et al, 2005;Magalhães et al, 2021). The identification of Pilumnus species based on adult morphology is not always an easy task, as some species are very similar (Takeda & Miyake, 1969;Melo, 1996).…”

“…The identification of Pilumnus species based on adult morphology is not always an easy task, as some species are very similar (Takeda & Miyake, 1969;Melo, 1996). As an example of systematic instability, Pilumnus vinaceus A. Milne-Edwards, 1880, previously considered to be a junior synonym of P. dasypodus by Rathbun (1897), was recently considered a valid species after a review based on integrative morphological and molecular data (Magalhães et al, 2021). The knowledge of the larval morphology can be an important accessory tool in the search for solutions to problems of this systematics, as for many other decapod (Barros- Alves et al, 2013;Clark & Cuesta, 2015;Magalhães et al, 2017).…”

“…Based on this scenario, the description of the first zoeal stage of the hairy crab P. vinaceus is provided. Pilumnus vinaceus is widely distributed in the Western Atlantic Ocean, where it occurs along the USA (Texas, Florida), Caribbean Sea, Antilles, and Brazil (Piauí, Ceará, Espírito Santo, Rio de Janeiro, São Paulo, Paraná, Santa Catarina) (Mantelatto et al, 2020;Magalhães et al, 2021). This species inhabits unconsolidated sand bottoms, as well as consolidated bottoms of rocks and, mainly, corals, from five to 20 meters (Melo, 1996).…”