Neotropical Nilothauma Kieffer, 1921 (Diptera, Chironomidae): Key, eleven new species, re-descriptions, new combination and new records Author Pinho, Luiz Carlos https://orcid.org/0000-0002-9153-9997 Laboratory of Systematics of Diptera, Department of Ecology and Zoology, Federal University of Santa Catarina, Campus Trindade, CEP 88040 - 900, Florianopolis, Brazil luizcarlospinho@gmail.com Author Andersen, Trond Department of Natural History, University Museum of Bergen, University of Bergen, P. O. Box 7800, NO- 5020, Bergen, Norway text ZooKeys 2021 2021-04-22 1033 81 125 http://dx.doi.org/10.3897/zookeys.1033.60686 journal article http://dx.doi.org/10.3897/zookeys.1033.60686 1313-2970-1033-81 BEFB015F4A354987AD10DFEB7D4F91DD 2E6467D3D0025F778A77798A4072BCB5 Beardius longissimus (Mendes & Andersen, 2009) comb. nov. Nilothauma longissimum Mendes & Andersen, 2009: 26 Material examined. Type material, as in Mendes and Andersen (2009) . Additional material. 8 males , slide-mounted: Brazil , Bahia , Camacan , RPPN Serra Bonita , Trilha Bapeba , 15°20'35"S , 39°33'34"W , 4.xi.2009 , light trap , A.R. Calor et al. leg . 3 males , slide-mounted, as previous, except: 15°23'32"S , 39°33'53"W , 2.xi.2009 . 1 male , slide-mounted, as previous, except: 03.ii.2009 . 1 male , slide-mounted, as previous, except: corrego 2, 15°23'10"S , 39°34'03"W , 819 m a.s.l., 01.viii.2008 , light trap, A.R. Calor, L.S. Lecci, L.C. Pinho & R.A. Moretto leg. 1 male , slide-mounted: Brazil , Sao Paulo , PE Serra do Mar , Ubatuba , Picinguaba , Camburi stream, 09.ix.2006 , light trap , M.R. Spies & A.E. Siegloch leg. Remarks. Pinho et al. (2013) found that the "presence of apical thin setae on inferior volsella" (character 74, state 1), i.e. a group of two, rarely three, slender simple setae at the very tip of the inferior volsella, in addition to subapical, stouter setae, is the only synapomorphy of Beardius Reiss & Sublette, 1985 in the adult stage. In fact, the character is shared by all species of Beardius and is not found elsewhere, except in Nilothauma longissimum Mendes & Andersen, 2009, a species that was considered to be sister to all remaining Nilothauma by Mendes and Andersen (2009) in a phylogenetic analysis with Paratendipes Kieffer and Pseudochironomus Malloch as outgroups. The comparatively-high antennal ratio in N. longissimum (AR> 1.00) is the only exception in Nilothauma , which generally have very low antennal ratios (AR <0.40). Further, the venarum ratio (VR) seems to be low in N. longissimum compared to other Nilothauma species; other characters in N. longissimum are consistent with the current diagnosis of Beardius . We therefore propose the new combination and emend the diagnosis of Nilothauma accordingly. Distribution. The species was originally described from Sao Paulo State, south-eastern Brazil by Mendes and Andersen (2009) ; the range is now extended to Bahia State in north-eastern Brazil.