Hydrobaenus Fries, 1830

Namayandeh, Armin, Hudson, Patrick L., Bogan, Daniel L. & Hudson, John P., 2024, Chironomidae (Diptera: Insecta) of Alaska, USA, with descriptions of new species and a checklist, Zootaxa 5511 (1), pp. 1-95 : 61

Hydrobaenus Fries, 1830

Saether (1976) reported three species of Hydrobaenus from Alaska, Hydrobaenus fusistylus (Goethghebuer, 1933) and Hydrobaenus laticaudus Saether, 1976 from the Cape Thompson area, and Hydrobaenus scapulapilosus Saether, 1976 from the Utqiagvik area. The Cape Thompson species were from the Watson et al. (1966) study, and they probably identified them as species of the genus Trissocladius Kieffer, 1908 , a closely related genus. The Point Barrow H. scapulapilosus was collected by P. D. Hurd in 1953. It is noteworthy that Saether (1976) suggested that this species could be Hydrobaenus pilipes ( Malloch, 1915) with further study of the various characters used to differentiate the two species. Hydrobaenus larvae have been collected from streams in Denali National Park ( Brabets & Ourso 2013) and St. Matthew Island ( Sikes et al. 2016). The St. Matthew’s larval material was identified to Hydrobaenus conformis group, which includes the species H. laticaudus , and Hydrobaenus lapponicus group, which includes H. fusistylus . There are also reports of Hydrobaenus larvae collected by the USDA research station in Palmer ( Arctos 2023). We collected larvae of H. pilipes group from a second order clearwater creek entering the Herbert River near Juneau.

Hydrobaenus larvae can be found in various habitats ranging from puddles to large rivers and emerge early in the spring, with only one generation per year ( Saether 1976). The adults typically mate on substrates, and the two sexes are usually observed in an end-to-end position. Larvae of several Nearctic species are known to aestivate over summer and resume development during the winter ( Cranston et al. 2007, Tucker et al. 2016).