The Echinoid Directory

• Test ovate; very thick-shelled.
• Apical disc with four gonopores.
• Anterior ambulacrum flush from ambitus adapically, but forming a deep sulcus beneath the ambitus to the peristome.
• Peristome small and circular; set rather far back from the anterior margin. Oblique and opening towards anterior.
• All ambulacra non-petaloid; pore-pairs small and undeveloped adapically.
• Plastron plating meridosternous with sternal plate followed by somewhat offset episternals. Probably disjunct.
• Aboral tuberculation fine and uniform.
• Periproct low on posterior truncate face; just visible in oral view.
• No fascioles.

Upper Cretaceous to Palaeocene, Europe.

Holaster sulcatus Cotteau, 1873, p. 170, by original designation.

• L. sulcatus (Cotteau, 1873); Cenomanian, France and Germany (includes Holaster stumcki Wollman).
• L. ennisi Smith & Wright, 2003; Cenomanian, UK.
• L. airaghii Lambert; Scaglia, Upper Cretaceous, Italy.
• L. dallagoi (Airaghi); Scaglia, Upper Cretaceous, Italy.
• L. cotteaui (Seunes, 1889); Maastrichtian; Pyrenees.
• L. palaeocenicus (Smith & Gallemi 1999); Palaeocene, Spain.

Holasteroida, basal Meridosternata.

Possibly paraphyletic by exclusion of Sternopatagus.

Differs from Stegaster in having no frontal groove. Differs from Basseaster in lacking a subanal fasciole and by its disjunct plastron. Sternopatagus also has a disjunct plastron, but has a marginal fasciole and paired episternal plates.

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.

Smith, A. B. & Wright, C. W. 2003. British Cretaceous echinoids. Part 7, Atelostomata, 1. Holasteroida. Palaeontographical Society Monographs, London. Pp. 440-568, pls 139-182.