A new species of Hypselaster (Echinoidea, Spatangoida) from the Middle Eocene Midawara Formation of the Eastern Desert, Egypt
Elattaar, A.A. (2018). A new species of Hypselaster (Echinoidea, Spatangoida) from the Middle Eocene Midawara Formation of the Eastern Desert, Egypt. Swiss Journal of Palaeontology 137(2): 379-387. https://dx.doi.org/10.1007/s13358-018-0156-y
In: Swiss Journal of Palaeontology. SPRINGER HEIDELBERG: Heidelberg. ISSN 1664-2376; e-ISSN 1664-2384, more
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| Keywords |
Schizasteridae Lambert, 1905 [WoRMS]
Marine/Coastal |
| Author keywords |
Schizasteridae; Lutetian; Mokattamian; Maghagha area; New species |
| Abstract |
The schizasterid echinoid genus Hypselaster Clark, 1917, is recorded for the first time from the Midawara Formation (Middle Eocene, Lutetian), which crops out east Maghagha area, east Nile Valley, Eastern Desert, Egypt. Except for Hypselaster sp. from the Upper Miocene (Messinian) of Morocco, no Hypselaster has been recorded in pan Africa. The material described in the present paper is considered to represent a new species (Hypselaster strougoi n. sp.) that is characterized by a medium, oval to subpentagonal test with distinct frontal sinus, a subcentral ethmolytic and wide apical disc (slightly behind the center of test) with two large and apart genital pores, an anteriorly excentric semilunal-shaped peristome, long, flexed and deeply sunken paired anterior petals, a longitudinally oval periproct in the topmost part of the oblique forwardly truncated posterior, and perforate, crenulated tubercles. Both peripetalous and incomplete latero-anal fascioles are present; the latero-anal fasciole is faint and incomplete laterally on the sides of the test. |
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