A new copopod: Mexiclopina campechana

Copepods are small, planktonic animals living both in the sea and in freshwater habitats. Cyclopoids are an order of copepods that is distinguished from other copepods by having shorter first antennae than the length of their head and body.

Cyclopoid copepods play an important role in aquatic food webs as either primary consumers or predators.  They often are also an important source of food for larval, juvenile, and adult fish of many species. Cyclopoids are intermediate hosts of many parasitic worms (tapeworms, cestodes, roundworms) that infect vertebrates, including humans.

The new species Mexiclopina campechana belongs to a new genus that was named after Mexico. The species is named after the state of Campeche in southeast Mexico, where the species was found.

For the experts: A new, monotypic genus of the interstitial marine cyclopoid copepod family Cyclopinidae G.O. Sars, 1913 is described from male and female specimens collected at Laguna de Términos, a large coastal lagoon system in the southern Gulf of Mexico. Mexiclopina campechana gen. et sp. n. cannot be adequately placed in any extant genus within the family. It differs from other cyclopinid genera in having a unique combination of characters including: 1) absence of modified brush-like seta on the mandibular exopod; 2) maxillule exopod with stout setal elements and brush-like setae absent; 3) basis of mandible with one seta; 4) presence of a modified seta on endopod of fourth leg; 5) fifth leg exopod unsegmented, armed with three elements in the female and five in the male; 6) intercoxal sclerite of first swimming leg with two medial spiniform processes on distal margin. The new genus is monotypic and appears to be most closely related to Cyclopina Claus, 1863 and Heptnerina Ivanenko & Defaye, 2004; the new species was compared with species of Cyclopina and it resembles C. americana Herbst, 1982 and C. caissara Lotufo, 1994. This is the second record of a species of Cyclopinidae in Mexico and the first in the Gulf of Mexico; the number of cyclopinid species recorded from the Americas is now 13.