Original paper
A new limulid (Chelicerata, Xiphosurida) from the Lower Jurassic (Sinemurian) of Osteno, NW Italy
Lamsdell, James C.; Teruzzi, Giorgio; Pasini, Giovanni; Garassino, Alessandro
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen Band 300 Heft 1 (2021), p. 1 - 10
67 references
published: Apr 29, 2021
manuscript accepted: Mar 6, 2021
manuscript received: Jan 26, 2021
ArtNo. ESP155030001000, Price: 29.00 €
Abstract
Fossiliferous beds within the Lower Jurassic (Sinemurian) Moltrasio Limestone at Osteno, Italy, preserve a marine fauna including crustaceans, ophiuroids, ammonites, vermiform invertebrates, chondrichthyans, and actinopterygians in Lagerstätte conditions. Excavations during the 1980s and 1990s have greatly expanded the known faunal diversity. Herein, we describe the first horseshoe crab from Osteno, representing the oldest Jurassic limulid and only the second xiphosuran known from Italy. The new taxon, Ostenolimulus latus n. gen., n. sp., preserves details of the external morphology along with phosphatized traces of internal muscles and book gills. A number of characteristics, most prominently the possession of a cardiac ridge with rounded cross section, indicate Ostenolimulus n. gen. is a limulid resolving outside of the crown group and belongs to a clade including other Jurassic and Cretaceous taxa, such as Mesolimulus, Allolimulus, Victalimulus, and Casterolimulus. The discovery of Ostenolimulus n. gen. indicates that stem limulids were a diverse and widespread clade during the Jurassic, a time when crown group limulids were beginning to diversify and radiate.
Keywords
Horseshoe crabs • Italy • Lagerstätte • Limulidae • taxonomy • Xiphosura