Allysson P. Pinheiro

Shrimps from the Santana Group (Cretaceous: Albian): new species (Crustacea: Decapoda: Dendrobranchiata) and new record (Crustacea: Decapoda: Caridea)

The fossil shrimp Araripenaeus timidus n. gen. n. sp. is the first fossil Penaeoidea from Brazil. Here, we describe, illustrate and compare it with Paleomattea deliciosa, a fossil Sergestoidea (Dendrobranchiata) previously described from the same region. The material of the early Cretaceous (Albian) was collected in the town of Jardim, south of the state of Ceará, in the superior septarian concretion level of the Romualdo Formation. Additionally, a second specimen of Kellnerius jamacaruensis was found in the same site of the Araripe Basin.

Large-field electron imaging and X-ray elemental mapping unveil the morphology, structure, and fractal features of a Cretaceous fossil at the centimeter scale.

We used here a scanning electron microscopy approach that detected backscattered electrons (BSEs) and X-rays (from ionization processes) along a large-field (LF) scan, applied on a Cretaceous fossil of a shrimp (area ∼280 mm(2)) from the Araripe Sedimentary Basin. High-definition LF images from BSEs and X-rays were essentially generated by assembling thousands of magnified images that covered the whole area of the fossil, thus unveiling morphological and compositional aspects at length scales from micrometers to centimeters. Morphological features of the shrimp such as pleopods, pereopods, and antennae located at near-surface layers (undetected by photography techniques) were unveiled in detail by LF BSE images and in calcium and phosphorus elemental maps (mineralized as hydroxyapatite). LF elemental maps for zinc and sulfur indicated a rare fossilization event observed for the first time in fossils from the Araripe Sedimentary Basin: the mineralization of zinc sulfide interfacing to hydroxyapatite in the fossil. Finally, a dimensional analysis of the phosphorus map led to an important finding: the existence of a fractal characteristic (D = 1.63) for the hydroxyapatite-matrix interface, a result of physical-geological events occurring with spatial scale invariance on the specimen, over millions of years.

On the type material of Scyllarides deceptor Holthuis, 1963 (Crustacea: Decapoda: Scyllaridae)

The only specimen listed in the original description of Scyllarides deceptor Holthuis, 1963 is the holotype from Sao Paulo, Brazil, presently housed in the Leiden Museum. From the original description, however, it is clear that the new species was actually based on a number of additional specimens. Six of them exist in the collections of the Museum of Zoology in Sao Paulo, and are shown herein to be paratypes of S. deceptor. Scyllarides deceptor and S. brasiliensis Rathbun, 1906, continue to be confounded with one another, in consequence of their very similar color patterns and locally sympatric distributions. As many as 251,786 tons of slipper lobsters have been landed in Santa Catarina between 2000 and 2007. These catches have been attributed to S. deceptor alone and did not take into consideration the existence of a second species in the area, S. brasiliensis. Correct recognition of slipper-lobster species will be critical to properly evaluate the lobster stocks in southeastern Brazil. An opportunity is taken herein to elaborate on the taxonomy of S. deceptor and S. brasiliensis.

A remarkable new genus and species of the planktonic shrimp family Luciferidae (Crustacea, Decapoda) from the Cretaceous (Aptian/Albian) of the Araripe Sedimentary Basin, Brazil

Abstract. A new genus and species of the planktonic shrimp family Luciferidae, Sume marcosi n. gen. n. sp., is described and illustrated from material collected in calcareous shale of the late Early Cretaceous (Aptian-Albian) Romualdo Formation, Araripe Basin, northeastern Brazil. The material is very well preserved, including the antennae, stalked eyes, second and third maxillipeds, pleopods, and uropods, and represents the first described fossil of the family Luciferidae.

Occurrence of Dendrocephalus brasiliensis Pesta, 1921 (Crustacea, Anostraca) in the Caras river, southern Ceara, Brazil

Occurrence of Dendrocephalus brasiliensis Pesta, 1921 (Crustacea, Anostraca) in the Caras river, southern Ceara, Brazil. The specimens were collected in March and April 2014. The new occurrence extends the distribution and update area of occupancy of the species, which is characterized by a specific habitat: temporary lakes.