Poikilolaimus floridensis n. sp. (Rhabditida: Rhabditidae) associated with termites (Kalotermitidae).
A survey of termite-associated nematodes was done in southern Florida to compare the diversity of such associations with other latitudes in the Neotropics. Six species (15 colonies) of termites (Isoptera) were collected from the field and eight species (15 colonies) from laboratory populations were examined for nematode associates. All six field-collected termite species, Cryptotermes cavifrons, Incisitermes snyderi, Neotermes jouteli, N. castaneus, Prorhinotermes simplex and Reticulitermes flavipes, representing two families (Kalotermitidae and, for the latter two species, Rhinotermitidae), were associated with nematodes. Nematodes were also isolated from laboratory populations of I. snyderi and Coptotermes formosanus. In total, seven putative species of nematodes were discerned using molecular bar-coding and culturing (when successful) including four rhabditids, one diplogastrid, Rhabditis rainai and a nematode that we are describing herein as Poikilolaimus floridensis n. sp. This nematode was isolated as dauer juveniles in the foregut of N. jouteli, N. castaneus and I. snyderi. It was recovered from workers, a soldier and an alate, suggesting internal phoresy. It is characterised by six triangular cuticular flaps covering the stomatal opening, simple tube-like stomatal structure, i.e., absence of teeth and glottoid apparatus, cuticularised and refractile secretory-excretory pore, conical male tail lacking 'bursa' or spike, short and conical female tail and didelphic female reproductive system. Poikilolaimus floridensis n. sp. is morphologically characteristic and does not easily fit the current genus definition of Poikilolaimus which is redefined herein. Molecular phylogenetic analysis based on near full length SSU ribosomal DNA sequence showed that the new species occupies a basal position in the genus.