The Echinoid Directory

Hypsopatagus Pomel, 1883, p. 31

[=Hypsospatangus Cotteau, 1890, p. 13 (nomen vanum); =Trachypneustes Munier Chalmas, 1890, p. 265; = Leiopneustes Cotteau, 1885, type species Brissus antiquus Agassiz, in Agassiz & Desor, 1847; = Leiopatagus Pomel, 1869 non Meyer, 1861; = Liopatagus Pomel, 1883, p. 30 ]

Diagnostic Features
  • Test cordiform with shallow frontal notch; tapering to rounded point posteriorly. Variable in profile with rather flat base.
  • Apical disc ethmolytic with four gonopores; the madreporic plate extending strongly to the posterior; subcentral.
  • Ambulacrum III weakly sunken from apex to peristome (deepest ambitally). Pore-pairs small and unspecialized.
  • Paired ambulacra petaloid; petals long and lanceolate, converging distally but remianing open. Pore zones slightly depressed but otherwise petals more or less flush.
  • Peristome at some distance from the anterior and slightly sunken; kidney-shaped and overarched by the labral plate. Phyllodes apparently well-developed.
  • Labral plate long and rather broad; extending to fourth ambulacral plate. Sternal plates rather narrow. Episternal plates paired and opposite and indented towards their rear by the ambulacral zones
  • Periproct situated on short posterior truncate face.
  • Peripetalous fasciole present; not indented behind anterior petals. No subanal fasciole according to Lambert & Thiery (1924).  However, specimen too worn to tell according to de Loriol (1891).
  • Aboral tuberculation heterogeneous with scattered tubercles over interambulacral and ambulacral zones.
Distribution
Upper Eocene and Oligocene, Europe, possibly elsewhere.
Name gender masculine
Type
Macropneustes meneghini Desor, 1858, p. 411, by original designation.
Species Included
  • Lambert & Thiery (1924) include a number of Eocene taxa, but until the type is better known, it is not certain how many are truly congeneric.
Classification and/or Status

Spatangoida, Micrasterina, Macropneustidae

?

Remarks
The oral plating in this taxon was described by de Loriol (1891) and shows it is a member of the Macropneustidae.  It differs from Trachypatagus in having a distinct anterior sulcus but like that taxon has the labral plate extending beyond the second adjacent ambulacral plate. While Lambert & Thiery (1925) suggested it had no subanal fasciole, the shape of the episternal plates clearly shows that it is descended from taxa that had a subanal fasciole, and its absence may simply be due to poor preservation.

The type species is very variable in profile.

De Loriol, P. 1891. Notes pir servir a l\'etude des echinodermes. Memoires de la Societe de Pphysique et d\'Histoire naturelle de Geneve. Volume Supplementaire, 1890, number 8, 31 pp, 3 pls.

Pomel, A. 1883. Classification méthodique et genera des Échinides vivante et fossiles. Thèses présentées a la Faculté des Sciences de Paris pour obtenir le Grade de Docteur ès Sciences Naturelles, 503, 131 pp. Aldolphe Jourdan, Alger.