A NEW SPECIMEN OF THE EXTINCT GHOST CRAB SPECIES OCYPODE ITALICA (DECAPODA: BRACHYURA: OCYPODIDAE) FROM THE PLIOCENE

OF TUSCANY (ITALY)

A. Di Cencio1,2,*_{, S. Casati}2 _{and A. Collareta}3

1_{Geologia e Paleontologia Technical Studio, San Casciano Val di Pesa, I-50026 Firenze, Italy.} 2_{Gruppo Avis Mineralogia e Paleontologia Scandicci, Badia a Settimo, I-50018 Scandicci, Italy.}

3_{Dipartimento di Scienze della Terra, Università di Pisa, I-56126 Pisa, Italy.}

*E-mail: andreadicencio@geologiaepaleontologia.eu

Keywords: Crustacea, ghost crabs, Mediterranean Basin, Piacenzian, Tuscany.

Well-preserved fossils of benthic marine invertebrates, including decapod crustaceans, are often found in the Pliocene sediments that constitute the substratum of the hills of Tuscany. Year after year, new or “exotic” taxa are thus found and documented, mostly thanks to isolated finds. In systematic paleontology, the ideal condition for instituting a new species is by working on many specimens: in this way, a newly instituted taxon may be described on the basis of the holotype and other specimens that would depict its intraspecific variability. That said, given the fragmentary nature of the fossil record, this happens rarely, and several extinct species are instituted and described based on very few specimens. It is the case for the ghost crab species Ocypode italica Garassino et al., 2010, which was known so far by the holotype and one paratype. Such a limited fossil record is typical of the Ocypode spp. and might reflect the habitat preferences of this group of ghost crab species, inhabiting high-energy sandy shores at tropical and subtropical latitudes worldwide. Among the Neogene record of decapod crustaceans from Italy, the two known specimens of O. italica are nonetheless of prime importance, as they represent the northernmost finds of the genus Ocypode in the Mediterranean Basin, as well as the geologically oldest species of Ocypode in Europe. Recently, thanks to the cooperation between some local amateurs and academically educated paleontologists, a well-preserved new specimen of O. italica has been collected from the same upper Pliocene deposits of Tuscany (central Italy) from which the type specimens originate. Our new find represents the third known specimen of this species, and as such, it allows to better characterize the anatomy of the carapace, chelipeds and walking legs of this rarely reported extinct form of ghost crabs. In particular, anatomical resemblances between O.

PALEOBIODIVERSITY OF QUATERNARY FOSSIL TETRAPODS IN CONTINENTAL PORTUGAL

D. Estraviz López1,2,* _{and O. Mateus}1,2

1_{Departamento de Ciências da Terra, FCT - Universide Nova de Lisboa, Caparica, Portugal.} 2_{Museu da Lourinhã, Lourinhã, Portugal.}

*E-mail: d.lopez@campus.fct.unl.pt // estravizlopez.dario@gmail.com

Keywords: census, representativeness, fossil record, Pleistocene, inventory.

Paleobiodiversity studies have been used to study the representativeness of the fossil record or to detect extinction events. The fossil fauna of the Quaternary is the most comparable to nowadays, thus can be used to test the representativeness of paleobiodiversity studies. However, studies of this type with Quaternary vertebrates are not widespread and usually focus into certain groups. On this work, an inventory of all tetrapod taxa scientifically published as fossils in the Quaternary of continental Portugal will be provided, thanks to an extensive bibliographical research. Then they will be compared with the current biodiversity for the same groups (Taking into account the introduced species); inferring rates of extinction and representativeness of the fossil record.

There are 176 tetrapod species recognized in the fossil record of the Quaternary of Portugal (7 amphibians, 13 non-avian reptiles, 80 birds and 74 mammals). 125 species (71%) still live in the country today, while 49 (29%) are only known as fossils; 29 (17%) are locally extinct and 20 (11%) globally extinct. The 125 species detected as fossil that still live in the country represent 38% of the total 332 species. Most findings come from cave deposits, without them, the representativeness falls to 35 species (10%). Amphibians and non-avian reptiles do not suffer any kind of extinction besides turtles. Bird modern biodiversity is much higher than its paleobiodiversity, only 30% of the modern species were detected as fossils. Mammals suffered a high level of extinction with almost half of them being locally or totally extinct.

OCCURRENCE OF CROCODYLUS IN THE EARLY MIOCENE MOGHRA FORMATION, NORTHWESTERN DESERT, EGYPT

M. A. Gawad1,_{*, L. Steel}2_{, J. Sertich}3_{, E. Miller}4_{, A. El-Barkooky}1_{, M. Hamdan}1_{, H. Sallam}5 and G. Gunnell6

1_{Cairo University, Faculty of Science, Geology Department, Egypt.} 2_{Natural History Museum United Kingdom, London, United Kingdom.}

3_{Denver Museum of Nature and Science, Denver, Colorado, U.S.A.}

4_{Wake Forest University, Anthropology Department, Winston-Salem North Carolina, U.S.A.}

5_{Mansoura University Vertebrate Paleontology Center (MUVP), Department of Geology, Faculty of Science, Mansoura}

University, Egypt.

6_{(Deceased) Division of Fossil Primates Duke Lemur Center, Durham, North Carolina, U.S.A.}

*E-mail: mkabdelgawad@sci.cu.edu.eg

Keywords: Moghra, Crocodylus, Rimasuchus, Tomistoma, Euthecodon.

Neogene African crocodylians, particularly from North Africa, are of critical to understand the origin and historical biogeography of African and European crocodylians. The Moghra Formation (Qattara Depression of the North Western Desert, Egypt) is characterized by sandstone and shale intercalations, which are related to a tide-dominated estuary environment within a tropical, warm climate. It is the best exposure formation along the Northern scarp of the Qattara Depression. The Moghra locality has an unusually high abundance and diversity of vertebrate fossils, due to the warm environment and proper conditions needed for fossilization, with records of mammals, reptiles, birds and even fishes. The vertebrate fossil remains are concentrated within four stratigraphic horizons, mainly of lag deposits. The crocodylian remains are concentrated just in the lowest horizon. The systematic study of the crocodylian remains has allowed us to reidentify and describe Crocodylus sp. alongside with other three crocodylians (Rimasuchus lloydi, Tomistoma dowsoni

and Euthecodon sp.). In addition, geological and paleontological significance indicate that the Moghra

Formation is known to be older than Gabal Zelten, in Libya, and of similar age to the deposits at Rusinga, in Kenya and Napak, in Uganda. Therefore, the fossil record of Crocodylus from the Moghra Formation might be the oldest form of Crocodylus in Africa. 


A PRELIMINARY REASSESSMENT OF THE RHINOCEROTID DIVERSITY