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Echinocardium olisiponensis Kotchetoff, Kotchetoff & Ferreira, 1975

Diagnostic Features	Test ovate with a shallow anterior sulcus. Test height is about one-half of test length. The apical disc lies slightly posterior of the centre. Ambulacrum III is narrow, slightly sunken adapically, increasingly so towards the ambitus; the pores are uniserial. The other ambulacra are very slightly depressed; pore zones Ib and IIa, respectively IVb and Va, as well as Ia and Vb do not form totally continuous arcs only because the inner fasciole interrupts those arcs. Inside the inner fasciole there are no obvious pores. In the lectotype, the right side of the subanal fasciole bears four enlarged pore-pairs (five ambulacral plates extending into the subanal fasciole) whereas its left side bears five enlarged pore-pairs (six ambulacral plates extending into the subanal fasciole). The inner fasciole is rather long, extending about two-thirds of the test length. The subanal fasciole is about as long as wide, slightly teardrop-shaped, pointing adorally and extending almost from the adoral margin of the periproct to the inferior margin of the test. The peristome is located about one-fourth of test length from the anterior margin. The transversely elongated periproct lies high on the test posterior face; it is visible in aboral view due to the obliquely truncated posterior end.
Distribution	Middle Miocene of Portugal.
Type	Holotype, Museu Geologico (Lisbon, Portugal) MG 3795a; syntypes MG 3611, 3614a-c 3630, 3789-91 and 3795b.
Classification and/or Status	A species of Echinocardium.
Remarks	Only two living species present an inner fasciole that extends about two-thirds of test length and have its paired petals greatly expanded adapically so that the pore zones Ib and IIa, respectively IVb and Va, form lateral arcs: E. cordatum and E. mediterraneum. E. cordatum differs from E. olisiponensis by its different organization of pores in the adapical part of ambulacrum III (offset into two irregular rows in E. cordatum and uniserial in E. olisiponensis), smaller area circumscribed by subanal fasciole and the number (four) of ambulacral plates extending into it, its narrower periproct, and its anal fasciole extending adapically from subanal fasciole. E. mediterraneum differs by the different pattern of its inner fasciole (maximum width immediately ahead of anterior poriferous zones of anterior paired petals), its well developed subanal heel, its narrower periproct, the smaller area circumscribed by its subanal fasciole and the number (four) of ambulacral plates extending into it and its anal fasciole extending adapically from subanal fasciole. E. orthonotum differs from E. olisiponensis by its more anteriorly displaced apical disc, shallower anterior ambulacrum, distinctly less inflated interambulacra, presence of four to five large pore-pairs within inner fasciole in posterior poriferous zones, three ambulacral plates extending into the subanal fasciole, anal fasciole extending adapically from subanal fasciole. E. marylandiense differs by its relatively wider and higher test, more anteriorly displaced apical disc, presence of three to five large pore-pairs within inner fasciole in posterior poriferous zones, less anteriorly displaced peristome, narrower periproct, presence of an anal fasciole. Kotchetoff, B; Kotchetoff, Y. & Ferreira, O. V. 1975. Contribution a la connaissance des gisement fossiliferes miocenes au Nord du Cap d'Espichel. Comunicaces dos Servicos Geologicos de Portugal, Lisboa, 59, 59-106, 8 pls. Pereira, P. 2010. Echinoidea from the Neogene of Portugal mainland. Palaeontos, Mortsel, 18, 154 pp, 37 pls.