The Echinoid Directory

• Test subglobular.
• Apical disc with five subequal genital plates; 5 gonopores; hydropores confined to genital plate 2 only.
• Ambulacra trigeminate throughout. Upper and lower elements in each triad compound plate are reduced in size and occluded from the midline; single occluded plates present in each triad adapically, two adorally.
• No ridges developed on internal face of the oral surface.
• Peristome small and central.
• Periproct as large as peristome, separated from the peristome by 1-2 interambulacral plates; extending to immediately beneath the ambitus, separating 7-8 interambulacral plates.

Late Cretaceous (Maastrichtian) of Cuba.

Echinoconus lanieri Cotteau, 1881, p. 11, by monotypy. Figured syntype: BMNH E4570.

• Only the type species.

Holectypoida, Holectypidae, Coenholectypinae.

Monotypic.

Although Mortensen (1948) stated that Lanieria had internal butressing, such structures cannot be found on specimens in the Natural History Museum. Lanieria closely resembles Metholectypus in shape, which is a probable junior synonym of Coenholectypus, although the unique specimen on which this is based is too poorly preserved to be certain. However, in Metholectypus occluded plates in the ambulacral zones are confined to the region close to the peristome.

Cotteau, G. 1881. Description des echinides fossiles de l'Ile de Cuba. Annales de la Societe geologique de Belgique 9 (Memoire 4), 1-49, pls 1-4.

Duncan, P. M. 1889. A Revision of the Genera and great Groups of the Echinoidea. Journal of the Linnean Society of London, Zoology, 23, 1-311.

Mortensen, T. 1948. A monograph on the Echinoidea, V. C. A. Reitzel, Copenhagen

Smith, A. B. & Jeffery, C. H. 2000. A key to Maastrichtian and Paleocene echinoids. Special Papers in Palaeontology 64, 1-404