Genus Natatolana Bruce, 1981

Natatolana Bruce, 1981: 957, Bruce 1986: 52, Brusca & Iverson 1985: 37, Botosaneanu et al. 1986: 412, Wetzer et al. 1987: 2, Brandt 1988: 102, Kensley & Schotte 1989: 139, Brusca et al. 1995: 74, Keable 2006: 139.

Type species. Cirolana hirtipes Milne Edwards, 1840; by original designation.

Genus remarks. Natatolana is similar to both Politolana and Dolicholana, although it can be readily distinguished from Politolana by the shape of pereopods 5–7. The basis in Politolana is narrow and has a few setae, while in Natatolana it is expanded and has many long plumose setae (Bruce, 1981). In Natatolana, in addition, the appendix masculina arises basally rather than sub-medially as observed in Politolana (Bruce, 1981). Natatolana also differs from Dolicholana in having the frontal lamina ventral surface entirely flat and not forming a 90° angle with the clypeus.

Natatolana is the second most diverse cirolanid genus, with 74 species, including one fossil form from the Lower Cretaceous (Bruce & Olesen 1995, Brusca et al. 1995, Keable & Bruce 1997, Keable 2006, Vegan et al. 2019). Natatolana species have been recorded in all the world’s oceans, and the cosmopolitan distribution if these isopods can be explained by their pelagic or partially pelagic way of life (Bruce 1981, Brusca et al. 1995, Bruce 2003). Natatolana species have mostly been recorded from the intertidal zone to depths of 1000 m, and only eight species are known to occur at depths of more than 1000 m, with Natatolana rekohu Bruce, 2003 reaching a depth of 2769 m off New Zealand, and Natatolana natalis (Menzies & George, 1972). However, Keable (2006) reported Natatolana from depths of around 6000 m, based on a specimen from the Peru-Chile Trench (USNM 120961), although its poor condition impeded the identification of the species.