The identity of Dactylocladius commensalis (Diptera: Chironomidae) revealed

Abstract

The chironomid species commensal on Blephariceridae described as Dactylocladius commensalis Tonnoir, 1923 from New Zealand has remained enigmatic since its first discovery. The taxon has not been restudied despite the apparent strong commensal/phoretic affinity of the aquatic immature stages with species of the common blepharicerid genus Neocurupira Lamb, 1913, especially species belonging to the hudsoni complex in which occurrence can reach 100% of all populations. The genus Dactylocladius Kieffer, 1906 is no longer meaningful because the type species is lost and of uncertain identity and is treated as a nomen dubium. Here the species is recognised from recently collected material by the congruence of morphology of all life history stages to the original description, and the tight association with torrenticole blepharicerid larvae. Phylogenetic analyses suggest that it is close to certain austral Orthocladiinae, namely Kaniwhaniwhanus Boothroyd, 1999, Botryocladius Cranston & Edward, 1999, Pirara Boothroyd & Cranston, 1995, and especially Naonella Boothroyd, 1994. A new genus, Tonnoirocladius gen. n. is established for the species Tonnoirocladius commensalis (Tonnoir) (comb. n.), since it differs substantially from the putative sister genus, the New Zealand Naonella.