A new species of Peltidium Philippi, 1839 (Crustacea, Copepoda, Harpacticoida) from the Pacific coast of Mexico

Abstract

During the analysis of phytal meiobenthic samples collected from a rocky-sandy beach in the state of Nayarit, in the Mexican Pacific, several specimens of harpacticoid copepods were obtained and taxonomically examined. These specimens were found to represent an undescribed species of the peltidiid genus Peltidium Philippi, 1839. The new species, Peltidium nayarit sp. n. is described herein. It resembles Peltidium nichollsi Geddes and Peltidium lerneri Geddes from Bahamas but also the widespread Peltidium speciosum Thompson & Scott and Peltidium purpureum Philippi. The new species from the Mexican Pacific differs from its known congeners by its possession of a unique combination of characters, including a modified pectinate seta on the antennary exopod, three terminal setae on the second endopodal segment of leg 1, third exopodal segment of leg 1 with three elements, inner terminal claw twice as long as outer claw, female fifth leg with 5 exopodal setae, exopodal setae I-III stout, spinulose and seta IV being as long as seta V. This is the second species of the family known to be distributed in the Eastern Tropical Pacific and in Mexico. Pending additional data, the distribution of this species appears to be restricted to this area of the Mexican Pacific.

First Record of the Family Peltidiidae (Copepoda; Harpacticoida) from the Gulf of Mexico, with the Description of a New Species ofPeltidium

“…The family Peltidiidae (Copepoda; Harpacticoida) contains mainly marine algaldwellers able to cope with strong water flows over flat surfaces thanks to their flattened bodies (Boxshall and Halsey 2004;Song et al 2015). The family is composed of eight genera (Boxshall and Halsey 2004), of which Peltidium , with 28 valid species, is the most speciose (Varela 2005;Wells 2007;Suarez-Morales and Jarquin-Gonzalez 2013;Varela and Gomez 2013). Members of Peltidium have been recorded from all but the polar seas (Song et al 2015).…”