Phylogenetic Revision of the Fish Families Luvaridae and †Kushlukiidae (Acanthuroidei), with a New Genus and Two New Species of Eocene Luvarids

Abstract

Ten synapomorphies are described that support the proposed sister group relationship of the Eocene Kushlukiidae and the Eocene to Recent Luvaridae as the superfamilial clade Luvaroidea at the node between the siganid and zanclid+acanthurid clades of acanthuroid fishes. The Kushlukiidae previously have been known only on the basis of <i>Kushlukia permira</i> Danilchenko from the Eocene of Turkmenistan, but another species of that age is shown to have been present in India; the latter is not given a new specific name because the two specimens of it are only fragments. In addition to the well known Recent species <i>Luvarus imperialis</i>, three fossil species have been referred to the Luvaridae: <i>Proluvarus necopinatus</i> Danilchenko from the Eocene of Turkmenistan is here recognied as a valid species of <i>Luvarus</i>, with <i>Proluvarus</i> becoming a junior synonym of <i>Luvarus; Eoluvarus bondei</i> Sahni and Choudhary from the Eocene of India is shown to be not a luvarid but, rather, a member of the fossil perciform family Exelliidae, the affinities of which family are poorly understood; <i>Luvarus praeimperialis</i> Arambourg from the Oligocene of Iran is shown to be not a luvarid but, rather, a representative of the new genus <i>Aluvarus</i> of such uncertain affinity that we simply place it incertae sedis among the percomorphs. Among the materials used by Danilchenko in the description of <i>Proluvarus necopinatus</i> only the holotype and the five other largest specimens (about 326-495 mm SL) represent that species. All of the other specimens are smaller than about 215 mm SL and represent two new species of a new genus of luvarid, <i>Avitoluvarus dianae</i> and <i>A. mariannae</i>. Numerous derived features are used to define both the Kushlukiidae and Luvaridae. Within the Luvaridae, the preponderance of derived features is found in <i>Luvarus</i>, whereas <i>Avitoluvarus</i> has only two unequivocal synapomorphies. The Luvaroidea, therefore, are represented by the Eocene Kushlukiidae with one genus and two species (<i>Kushlukia permira</i> and <i>K.</i> sp.) and the Luvaridae with one Eocene genus with two species (<i>Avitoluvarus dianae</i> and <i>A. mariannae</i>) and one genus, <i>Luvarus</i>, with one Eocene species, <i>L. necopinatus</i>, and one Recent species, <i>L. imperialis</i>.