Bothriolepis, Sergeymoloshnikov, 2004

Sergeymoloshnikov, 2004, Crested antiarch Bothriolepis zadonica H. D. Obrucheva from the Lower Famennian of Central European Russia, Acta Palaeontologica Polonica 49 (1), pp. 135-146 : 136-137

Genus Bothriolepis Eichwald, 1840 Bothriolepis zadonica H.D. Obrucheva, 1983 Bothriolepis sp.nov. O.P.ObruchevaandH.D. Obrucheva1977:27.pl.

1: 1; H.D. Obrucheva 1980b: 95. Bothriolepis sp. 1 H.D. Obrucheva 1980a: 42. Bothriolepis sp. 2 H.D. Obrucheva 1980a: 42. Bothriolepis zadonica H.D. Obrucheva 1983: 37–40 , figs. 1, 2;

Moloshnikov 2001a: 37; Moloshnikov 2001b: 32. Holotype: Anterior median dorsal plate PIN 1660/3.

Diagnosis.—Large bothriolepidid placoderm, L of the head and trunk shields up to 40 cm. Flattened head shield hexagonal and wide and having straight rostral and lateral margins. Rostral margin of head shield wide. Upper infraorbital groove runs midway between lateral and orbital margins and one third of distance between rostral and orbital margins closer to rostralone. The preorbital recess of head shield very large and occupies almost up to the middle of premedian plate L. Angle between facial lamina and nasal one of premedian plate equals 60–80°. Preorbital recess of “trapezoid” type. Rough supraotic thickening of head shield very large, W of nuchal plate/W of supraotic thickening index equals about 2. Anterolateral corners of otico−occipital depression narrow at the base and only slightly expressed. Prespiracular (or lateral) pits at the internal surface of head shield absent. Trunk shield deep and narrow, with deep median dorsal crest. Anterior dorsolateral and mixilateral plates wide. Plates are ornamented by tubercles (adults), tubercles and ridges (subadults) or only ridges (juveniles). Lateral margin of pectoral appendages bears high tubercles.

Stratigraphical and geographic distributions.— Upper Devonian, Lower Famennian, Zadonskian Regional Stage, Central European Russia, Orel and Tver Regions .