615 ISSN 0031-0301, Paleontological Journal, 2008, Vol. 42, No. 6, pp. 615–620. © Pleiades Publishing, Ltd., 2008. Original Russian Text © A.F. Bannikov, J.C. Tyler, 2008, published in Paleontologicheskii Zhurnal, 2008, No. 6, pp. 43–48. INTRODUCTION We recently (Bannikov and Tyler, 2008) discussed the importance of the excavations near Gorny Luch in the Northern Caucasus in greatly improving our knowl- edge of the diversity of marine fishes of the Middle Eocene, including that for taxa of the order Tetraodon- tiformes. Gorny Luch is becoming just as important for understanding tetraodontiform historical diversity as has been the classic Eocene marine fish locatily of Monte Bolca, Italy. We herein describe from Gorny Luch another important addition to the fossil tetraodon- tiform fishes, that of the first Eocene record for the trig- gerfish family Balistidae, which family has previously been known only as early as the Oligocene (Rupelian of the Caucasus and Switzerland). The uppermost Middle Eocene new genus and spe- cies, Gornylistes prodigiosus, is thoroughly modern in its morphology and appearance, just as much so as the several balistid taxa already known from the Oligocene and more recent periods. In the uppermost Paleocene and lowermost Middle Eocene that are older than that at Gorny Luch (uppermost Middle Eocene, Kuma Hori- zon), there are several stem taxa of the balistoid + ostra- cioid clade and thereby distantly related to the true Bal- istidae, but the new genus and species from Gorny Luch is by far the earliest known unquestioned member of the Balistidae. SYSTEMATIC PALEONTOLOGY Family Balistidae Rafinesque, 1810 Genus Gornylistes Bannikov et Tyler, gen. nov. E t y m o l o g y. The generic name combines that of Gorny , the first name in the type locality, with listes, the last two syllables in the classic generic name Balistes from the Recent fauna, the genotype of the family; masculine. Type species. Gornylistes prodigiosus sp. nov. D i a g n o s i s. The new genus is unique among all balistids, both fossil and Recent, by the following: supraneural carina strut vertically oriented and articu- lating with carina distinctly posterior to vertical level of base of third dorsal fin spine; long posterior projection of distal end of pelvis (basipterigium) beyond dorsal lobe, with encasing scales well separated from region of dorsal lobe; distance between bases of second and third dorsal fin spines relatively great (6.9 times in stan- dard body length = SL); width of base of first dorsal fin spine relatively slender in proportion to length of carina (9.6 times in carina length). S p e c i e s c o m p o s i t i o n. Type species. C o m p a r i s o n. In all balistids (and only balistids among all tetraodontiforms), there is a sturdy supraneu- ral strut (presumably a modified dorsal fin basal ptery- giophore) that supports the posterior end of the carina that bears the three dorsal fin spines. This supraneural strut in Gornylistes prodigiosus is oriented vertically and it contacts the lower posterior region of the carina at a point distinctly posterior to the level of the base of A New Genus and Species of Triggerfish from the Middle Eocene of the Northern Caucasus, the Earliest Member of the Balistidae (Tetraodontiformes) A. F. Bannikov a and J. C. Tyler b a Paleontological Institute, Russian Academy of Sciences, Profsoyuznaya ul. 123, Moscow, 117997 Russia e-mail: aban@paleo.ru b National Museum of Natural History, Smithsonian Institution (MRC-106), P.O. Box 37012, Washington DC, 20013-7012 United States e-mail: tylerj@si.edu Received October 5, 2007 Abstract—Until now, the earliest known members of the triggerfish family Balistidae have been two genera from the Oligocene. Herein is described the new balistid Gornylistes prodigiosus gen. et sp. nov. from the uppermost Middle Eocene (Kuma Horizon) of the Northern Caucasus (Gorny Luch locality); it is as thoroughly modern in its bauplan as the taxa of balistids from the Oligocene and more recent periods, and far more advanced morphologically than the several stem taxa of the balistoid + ostracioid clade known from earlier in the Middle and Lower Eocene and from the Upper Paleocene. DOI: 10.1134/S0031030108060075 Key words: Tetraodontiformes, Balistidae, new taxa, Middle Eocene, Northern Caucasus, Russia.