The Echinoid Directory

Mariania Airaghi, 1901, p. 211

[=Airaghia Lambert, 1910, p. 3 (nom. van.)]

Diagnostic Features	Test cordate with shallow, broad anterior sulcus; domal in profile with steep sides and flat base. Posterior face short and distinctly undercut. Apical disc ethmolytic with four gonopores - plating unknown; central. Anterior ambulacrum with wide, gentle sulcus. Pore-pairs small and undifferentiated aborally (no funnel-building tube-feet). Paired ambulacra petaloid and flush to very slightly depressed; long and open distally; slightly bowed; interporal zone wide. No occluded plates at ends of petals Peristome large and wide; close to anterior border and facing forward into frontal groove. Labrum projecting to extend over peristome in oral view. Labral plate long and wedge-shaped; extending to midway down the second ambulacral plate. Sternal plates triangular with vertical median suture; fully tuberculate. Episternal plates hardly contracted to the posterior, weakly offset. Periproct on posterior truncate face; transverse; visible in oral view. No peripetalous fasciole; possibly a narrow bilobed subanal fasciole passing across the middle of plates 3a and 3b in the posterior interambulacrum (but preservation poor). Three small subanal pore-pairs weakly developed. Aboral tuberculation heterogeneous; scattered primary tubercles are crenulate and flush.
Distribution	Miocene, France, Corsica and Sardinia.
Name gender	feminine
Type	Macropneustes marmorae Desor, in Agassiz & Desor 1847, p. 9(115), by original designation.
Species Included	Lambert & Thiery (1921, p. 444) list two other possible species as congeneric. M. marmorae (Desor, 1847); Miocene (Burdigalian), Corsica M. deydieri (Cotteau, 1897); Burdigalian, Austria and France
Classification and/or Status	Spatangoida, Micrasterina, ?Maretiidae. Unknown.
Remarks	This taxon differs from Spatangus in having and elongate, wedge-shaped labral plate and short sternal plates. Furthermore in Spatangus the episternal plates do not markedly narrow to the rear whereas the episternal plates of Mariania are quite strongly indented to the rear by ambulacral plate 6. Philippe (1998, p. 213) regarded Mariania as a subgenus of Spatangus, but the labral plate is very different in shape and extend, extending to the rear of ambulacral plate 2 in Mariania. Both Philippe (1998) and Kroh (2005) give detailed descriptions of Mariania deydieri (Cotteau). It seems likely that it belongs to the Maretiidae rather than the Spatangidae given its plastron structure. Cotteau, G., in Locard, A, 1876. Description de la Faune des Terrains Tertiaires moyens et superieures de La Corse. Annales de La Societe d'Agriculture Histoire Naturelle et Arts Utiles de Lyon 9, 4, 3-380 pls 1-27 Cotteau, G. in Loccard, A. 1877. Description de la faune des Terrains Tertiares moyens de la Corse. F. Savy, Paris. Cotteau, G. 1884. Paleontologie Francaise. Terrains Tertiares II, Echinoidea Eocene. V. Masson, Paris. Kroh, A. 2005. Catalogus fossilium Austriae. Band 2. Echinoidea neogenica. Verlag der Osterreichischen Akademie der Wissemschaften. 210 pp., 82 pls. Philippe, M. 1998. Les echinides Miocenes du Bassin du Rhone: revision systematique. Nouvelles Archives, Museum d'Histoire Naturelle de Lyon 36, 1-441.