The Echinoid Directory

• Test ovate with modest anterior sulcus; depressed in profile with flat base and low, moderately sharp ambitus.
• Apical disc ethmolytic, with 4 gonopores; genital plate 2 projects to the posterior of the posterior oculars.
• Anterior ambulacrum in modest groove that deepens towards ambitus; pore-pairs apparently undifferentiated.
• Paired ambulacra petaloid and flush. Anterior paired petals bowed with pore-pairs in anterior column rudimentary throughout; those in posterior column large and conjugate. Posterior petals bowed to lanceolate, converging distally; shorter than the anterior petals.
• Periproct on short vertically truncate face; wider than tall.
• Peristome wider than long; kidney-shaped; only a little anterior of centre.
• Labral plate probably narrow and elongate. Sternal plates triangular with tubercles confined to posterior part (probably an artefact of preservation).
• Aboral tuberculation heterogeneous with scattered coarse tubercles in all but the posterior interambulacrum. Primary tubercles apparently sunken.
• Well-developed bilobate subanal fasciole; no peripetalous fasciole.

Middle to Upper Eocene, Europe.

Atelospatangus transylvanicus Koch, 1885, p. 115, by original designation.

• A. gardinalei (Oppenheim, 1889); Upper Eocene, Hungary, Italy.
• A. magnus Szorenyi 1963; Middle Eocene, Hungary.
• A. transilvanicus Koch, 1884; Upper Eocene, Hungary.
• A. grandituberculatus (Lewis, 1989); Upper Eocene (Bartonian), UK.

Spatangoida, Micrasterina, Loveniidae.

Presumed monophyletic.

Szorenyi (1963) provides a detailed revision of this genus. Distinguished from all other genera by the complete absence of petaloid pore-pairs in the anterior column of the anterior petal. The original diagrams appear to show tuberculation confined to the posterior part of the plastron, which was emphasised by Mortensen (1951) as a distinctive feature. However, material assigned to this species by Szoreyni (1963) has fully tuberculate sternal plates.

Closest to Semipetalon which differs in possess some petaloid pore-pairs at the distal ends of the anterior column of the anterior petals.

Koch, A. 1885. Mitteilungen aus dem  Jahrbuch der kgl. Ungarischen geolischen Anstalt 7, p. 115.

Mortensen, T. 1951. A monograph of the Echinoidea. V.Spatangoida 2. C. A. Reitzel, Copenhagen.

Szorenyi, von E. 1963. Einiges uber Mitlieder der Familie Spatangidae (Echinoidea). Palaeontologische Zeitschrift, 37, 185-197, pls 14-15.

Lewis, D. N. 1989. Fossil Echinoidea from the Barton Beds (Eocene, Bartonian) of the type locality at Barton-on-Sea in the Hampshire Basin, England. Tertiary Research 11, 1-47 [described under Spatangus].