New data on Beurlenia araripensis Martins-Neto & Mezzalira, 1991, a lacustrine shrimp from Crato Formation, and its morphological variations based on the shape and the number of rostral spines

Abstract

Fossil freshwater carideans are very rare worldwide. Here, we present new taxonomic remarks about Beurlenia araripensis from the Early Cretaceous laminated limestones of the Crato Formation, Araripe Basin, northeastern Brazil. We analyzed five fossil samples, testing the morphological variations such as, rostrum with 5 to 14 supra-rostral spines and 2 to 3 sub-rostral spines, which appears as serrate for Caridea. This variation demonstrates a morphologic plasticity also seen in extant species of the group, such as those of the genera Macrobrachium and Palaemon.

New Cretaceous (Aptian/Albian) boxer shrimp (Crustacea, Decapoda, Stenopodidea) from the Araripe Sedimentary Basin, NE, Brazil

“…The quality of the preservation of the single specimen of Dubiostenopus parvus n. gen. n. sp. is not as good as observed in other species found in the Araripe Sedimentary Basin, such as specimens of Beurlenia araripensis [ 26 , 27 ]. Nevertheless, Dubiostenopus parvus n. gen. n. sp.…”

“…sp.). Also, B. araripensis is a much larger species, with different degrees of ornamentation of the rostrum [27] and well-developed eyestalks, differing considerably from Dubiostenopus parvus n. gen. n. sp. Other fossil shrimps from Brazil are from different epochs than Dubiostenopus parvus n. gen. n. sp.…”