The Echinoid Directory

Paralampas Duncan & Sladen, 1882, p. 72

Diagnostic Features	Test thin-shelled, medium sized, subquadrate in outline, somewhat inflated, adoral surface flat to slightly pulvinate. Apical system anterior, monobasal with four genital pores. Petals broad, equal poriferous zones, bowed and closing distally. Periproct supramarginal, with slight aboral canopy and shallow but distinct subanal invagination. Peristome anterior, pentagonal, wider than high; bourrelets confined to vertical walls forming entrance to the peristome, slightly swollen. Phyllodes broad, single pored, with just two well developed series of pores in each ambulacrum in the type species, plus one or two inner pores; buccal pores present. Distinct granular tubercle-free zone between the peristome and the posterior surface.
Distribution	Palaeocene; Africa, India.
Name gender	feminine
Type	Paralampas pileus Duncan & Sladen, 1882, by subsequent designation of Lambert & Thiery, 1921, p. 371.
Species Included	Paralampas pileus Duncan & Sladen, 1882; Early Thanetian, Pakistan. Paralampas rancureli Tessier & Roman, 1973; Late Thanetian, Ivory Coast.
Classification and/or Status	Irregularia; Cassiduloida; Cassidulidae.
Remarks	Paralampas was originally established for a Thanetian species from Pakistan. The type species differs from Petalobrissus setifensis in a number of small but consistent ways. It has a monobasal apical system, whereas Petalobrissus has a tetrabasal apical system. Secondly, the oral surface is consistently flatter than in Petalobrissus, where the test is always depressed towards the peristome and rounded towards the margins. Thirdly, the anterior petal is longer than the other petals. However, it has a broadly similar test form and is undoubtedly closely related (Smith & Wright, 2000). P. M. Duncan & W. P. Sladen. 1882. The fossil Echinoidea from the Ranikiot Series of Nummulitic strata in western Sind. Palaeontologica Indica, 14th series 1 (3), 21-100, pls. 5-20. P. M. Kier. 1962. Revision of the cassiduloid echinoids. Smithsonian Miscellaneous Collections 144 (3) 262 pp. A. B. Smith & C. H. Jeffery. 2000. Maastrichtian and Paleocene echinoids: a key to world faunas. Special Papers in Palaeontology 63, 406 pp.