Elopothrissus bernardlemorti Lin & Nolf & Steurbaut 2022, sp. nov

Autor: Lin, Chien-Hsiang, Nolf, Dirk
Rok vydání: 2022
Předmět:
DOI: 10.5281/zenodo.6490965
Popis: Elopothrissus bernardlemorti sp. nov. urn:lsid:zoobank.org:act: EC4517DA-4346-4D6D-9875-6D79D11AA044 Fig. 8C–D Diagnosis OL/OH = 2.21–2.47, OsL/CaL = 0.43–0.55. Otoliths very elongate, thin, higher in the middle. Oval ostium with colliculum. Elongate cauda of about ½ OL with crest like crista superior. Etymology This species is named after the owner, Bernard Lemort, of the bar L’Espérance near the IRSNB where many innovative discussions have taken place among researchers, with excellent drinks, continuously inspiring the authors. Material examined Holotype UNITED STATES OF AMERICA • Right otolith; Texas, Alabama Ferry; “Stone City beds”; Fig. 8C; IRSNB P 9959. Paratypes UNITED STATES OF AMERICA • 5 otoliths, of which one is figured: Fig. 8D; Texas, Stone City Bluff, Brazos River; “Stone City beds”; IRSNB P 9960. Type locality and horizon United States of America, Alabama Ferry (Texas), “Stone City beds”. Dimensions of the holotype Length = 8.20 mm; height = 3.68 mm; thickness = 1.27 mm. Description This species is characterized by thin, very elongate otoliths which are obtuse at both ends, but the anterior one is more pointed. The deepest part of the otoliths is in their central part, which feature is most evident in the holotype. All the margins are smooth. The inner face is very slightly convex and the outer face is nearly flat. The sulcus is well-divided into ostium and cauda and opens widely antero-dorsally on the anterior rim. A large and oval ostial colliculum fills the ostium. The ostial crista superior curves markedly upwards. The cauda is long and straight, without colliculum. The caudal crista superior is more developed than the crista inferior and markedly constricted and ventrally bent in the posterior part. The crista inferior is almost straight without constriction. The ventral area is larger than the dorsal one. Remarks The otoliths of this new species are clearly different from those of the more commonly co-occurring Pterothrissus umbonatus (Koken, 1884) (see below) by their slender appearance. Schwarzhans (1981a) indicated Pterothrissus protensus Stinton, 1975, a junior synonym of Pterothrissus tardinensis (Leriche, 1908) (see Nolf & Rundle 2018: 19), as the type species of Elopothrissus. The otoliths of E. tardinensis are thicker and much more convex on the outer face than those of E. bernardlemorti sp. nov. Stratigraphic and geographic distribution Lutetian: “Stone City beds”, Texas. Bartonian: “upper” Lisbon Formation, Alabama.
Databáze: OpenAIRE