Prototherium montserratense (†)?

Fossil bones from a sirenia discovered in year 2011 in a cut rock of the quarry of Montlleó (Castellgalí). Several vertebras (V) and ribbons (C) are seen. The rock is a biocalcarenite from the geological bed Santa Maria, from marine origin in Bartonian of Eocene period, approx. 40 million years ago.

Sirenia is an order of mammal related to the elephants which came back to water life as the Cetacea. They’ve a big, round body like a seal, front extremities turned to wings, they lack of back extremities (though having vestigial bones into the body) and one tail turned to caudal wing. The sirenia were common in water in Tertiary period. However, at present just 5 species survive in shrinking distribution areas, being the Florida manatee (Trichechus manatus) the best known.

In 1982, Isidre Gurrea found another fossil of sirenia in a similar rock type in Mas Enric of Sant Cristòfol (Castellbell i el Vilar), in slope north of Montserrat. The bones were quite complete and still in anatomic position. In 1985 the rests were dug out in several blocks of rock; otherwise, if complete isolation was attempted, they would’ve been damaged. The blocks were stored in the Museum of Geology of Seminary of Barcelona, under the supervision of the palaeontologist Mn Lluís Via. In 1989, Giorgio Pilleri, Josep Biosca & Lluís Via published the monograph The Tertiary Sirenia of Catalonia that identifies the individual as the new species Prototherium montserratense (†), the sirenia of Montserrat. After several idle years, the Museum of Geology worked in the restoration of the fossil. Finally, since 2013 the sirenia of Montserrat is in display in the Museum of Geology of Seminary of Barcelona. The issue of May 2013 of the publication of Palaeontology Scripta is devoted to the sirenia of Montserrat, reporting its full history from discovery to display, with dig and study in between.

Likely the fossil from the quarry of Montlleó is same species as the one from Mas Enric, Prototherium montserratense (†), the sirenia of Montserrat.

[photo Florenci Vallès, drawing Josep Biosca]