The Echinoid Directory

Hypsoclypus Pomel, 1869, p. 25

[=Conolampas A. Agassiz, 1883, p. 48, type species Conoclypus sigsbei A. Agassiz, 1878; =Libyolampas Lambert, 1914, p. 112, type species Echinolampas africanus de Loriol, 1880; =Heteroclypeus Cotteau, 1891, p. 194, type species Galerites semiglobus Lamarck, 1816; =Scutolampas Lambert, 1906, p. 33, type species Conoclypus lucae Desor in Agassiz Desor, 1947 (objective) ]

Diagnostic Features
  • Test large, subcircular, domed, adoral surface flat.
  • Apical system monobasal, with small ocular plates.
  • Petals long, extending almost to margin, broad, with slight asymmetry. Interporiferous zones four times the width of poriferous zones; pores slightly conjugate, outer pore of pore-pair slightly elongated transversely, inner pore round; poriferous zones of unequal length, more pore-pairs in in right zone of petal III, posterior zones of petal II and IV, and outer zones of petal V and I; petals straight, with no tendency to close distally.
  • Periproct on the flat oral surface, transverse.
  • Peristome, slightly anterior, transverse, pentagonal.
  • Bourrelets weakly developed. forming steeply sloping entrance to peristome.
  • Phyllodes well developed, slight broadening near peristome, single pored, with many pore-pairs arranged in three series in each half-ambulacrum.
  • Buccal pores present.
Eocene to Recent of Europe, North Africa and the West Indies.
Name gender masculine
Conoclypus plagiosomus Agassiz, in Agassiz & Desor, 1847, p. 168 (= Conoclypus lucae Desor in Agassiz & Desor, 1847, p. 168, by subsequent designation of Lambert & Thiery, 1911, p. 375 (see Kier, 1962, p. 111, Philippe, 1998, p. 100).  The type specimen is R53 (a mould of specimen c278 in the University of Lyon Palaeontological Collections, Michelin collection).
Species Included
  • H. lucae (Desor in Agassiz & Desor, 1947); Miocene, circum-Mediterranean.
  • H. sigsbei (A. Agassiz, 1878); Recent West Indies.
  • H. africanus (De Loriol, 1880); Eocene, Egypt.
  • H. diomedeae (Mortensen, 1948); Recent, Philippines.
  • H. malayana (Mortensen, 1948); Recent, Kei Islands, Indonesia.
  • H. murrayana (Mortensen, 1948); Recent, Maldives.
  • H. hemisphaericus (Gregory, 1891); Helvetian, Malta.
  • H. semiglobus (Lamarck, 1816); Tortonian-Helvetian, Europe.
Classification and/or Status
Irregularia; Cassiduloida; Echinolampadidae.

Hypsoclypus is distinguished from Echinolampas by its long open parallel petals that are only slightly asymmetrical, its circular ambital outline, and its distinctly flat oral surface, where the periproct is situated.

Hypsoclypus is very similar to Heteroclypeus, to the extent that they are treated here as subjective synonyms.

Conoclypus plagiosumus has previously been considered to be the type species of this genus. Kier (1962, p. 112) states that C. plagiosomus is a junior subjective synonym of C. lucae as Agassiz\'s (1840, p. 5) C. plagiosomus is a nomen nudum.

P. M. Kier. 1962. Revision of the cassiduloid echinoids. Smithsonian Miscellaneous Collections, 144 (3) 262 pp.

T. Mortensen. 1948. A monograph of the Echinoidea: 4 (1): Holectypoida, Cassiduloida. Reitzel, Copenhagen, 363 pp., 14 pls.

M. Philippe 1998. Les echinides Miocenes du Bassin du Rhone: Revision systematique. Nouv. Arch. Mus. Hist. nat. Lyon 36, 1-441, pls 1-26.

Pomel, A. 1869. Revue des échinoderms et de leur classification pour servir d’introduction à l’étude des fossiles, 67 pp. Deyrolle, Paris.