The Echinoid Directory

Heterobrissus Manzoni & Mazzetti, 1878, p. 354

[=Archaeopneustes Gregory, 1892, p. 163, type species Paleopneustes hystrix Agassiz, 1880; ?=Brissolampas Pomel, 1883, p. 31, type species Palaeopneustes conicus Dames, 1877; ?=Pygospatangus Cotteau, 1888, type species Pygospatangus salvae Cotteau, 1877 ]

Diagnostic Features
  • Test ovate without anterior sulcus; posterior face truncate. Test domed in profile.
  • Apical disc ethmolytic, reportedly with four gonopores; somewhat anterior of centre.
  • Anterior ambulacrum narrow, flush; pore-pairs minute.
  • Paired ambulacra subpetaloid; enlarged pore-pairs extending almost to ambitus; parallel-sided and open distally.
  • Peristome facing forward into frontal groove. Labrum projecting to cover peristome in oral view; perioral area sunken.
  • Phyllodes very well developed.
  • Plastron plating unknown in type species.
  • Periproct marginal to inframarginal; circular and flush.
  • No fascioles.
  • Aboral surface covered in coarse and heterogeneous tuberculation.
  • Posterior ambulacra on oral surface covered in tubercles behind phyllodes.
Oligocene, Puerto Rico, Miocene, Italy, Cyprus; Recent, Indo-Pacific and Caribbean.
Name gender masculine
Heterobrissus montesi Manzoni & Mazzetti, 1878, p. 354, by original designation.
Species Included
  • H. montesi Manzoni & Mazzetti, 1878; Miocene, Italy [=H. cypriotes Currie, 1935; Miocene, Cyprus].
  • H. niasicus (Doderlein, 1901): Recent, Indo-Pacific.
  • H. hemingi (Anderson, 1902): Recent, Laccadive Sea.
  • H. hystrix (Agassiz, 1880): Recent, Caribbean.
  • H. elegans (Jackson); Oligocene, Puerto Rico.
Classification and/or Status

Spatangoida, Paleopneustina, Incertae sedis B.

Presumed monophyletic.


Mortensen (1950) separated Heterobrissus from Archaeopneustes by its marginal rather than inframarginal periproct and by the fact that the labrum extends to only the second ambulacral plate, not the third. However, this last point is unknown in the type species, and difference in the position of the periproct is minor. The two are undoubtedly closely related. Stefanini (1908) refigured the syntype material and showed Heterobrissus to have an inframarginal periproct, like that of Archaeopneustes. The two therefore are best treated as synonymous.

Pygospatangus Cotteau, 1888, is also possibly closely related, but is based on a poorly known Eocene species. It differs in having a thicker test, and a modern description of this taxon is needed before its true affinities can be ascertained.

Manzoni, A. & Mazzetti, G. 1878. Echinodermi nuovi della Molassa Miocenica di Monteso nella Provincia di Modena. Atti di Società Toscana di Scienze Naturali 3 (2), 350–356 [for 1877].

Mortensen, T. 1950. A monograph of the Echinoidea V Spatangoida 1. C. A. Reitzel, Copenhagen.

Stefanini, G. 1908. Echinidi del Miocene Medio dell\'Emilia. Palaeontographia italica 14, 65-119, pls 13-16.