Genre   Eurypatagus Mortensen,1948, p.133

Contributions to the Biology of the Philippine Archipelago and adjacent regions. Report on the Echinoidea collected by the United States Fisheries Steamer "Albatross" during the Philippine Expedition, 1907-1910. Part 3: The Echinoneidae, Echinolampidae, Clypeastridae, Arachnidae, Laganidae, Fibulariidae, Urechinidae, Echinocorythidae, Palaeostomatidae, Micrasteridae, Palaepneustidae, Hemiasteridae, and Spatangidae

Espèce type  Eurypatagus ovalis Mortensen, 1948, p.133 (désignation originale)

ibid.

Extension stratigraphique (bibliographique, non vérifiée) : Actuel

EURYPATAGUS, new genus

     Test low, arched : oral side flat, but sunken at the peristome. Outline elliptival, no groove or depression in the frontal edge ; the posterior end slightly produced. Paired ambulacra distinctly petaloid, continuing to the edge of the test, open distally ; frontal ambulacrum very narrow, the pores very small. The phyllodes of the anterior paired ambulacra very conspicuous, with 12-14 pores (tube feet) in each series, each accompanied by a sphaeridium. Peristome broad, pentagonal, rather far from the anterior edge. Labrum well developed, with a narrow posterior prolongation ending off the middle of plates No. 4 of the adjoining ambulacral series. Plastron very small, entirely naked, or at most with a very few tubercles (spines) at the posterior end. The 3 or 4 ambulacral plates adjoining the episternal plates adproctally prolonged, indicating the presence of a subanal fasciole in the young specimens ; but there is no trace of such fasciole in the adults. No internal or peripetalous (or marginal) fasciole. Periproct placed vertically on the posterior end of the test, somewhat  produced upward and visible from above. Apical system anterior; 4 genital pores. Primary tubercles of the aboral side not very conspicuous, scattered all over the interambulacra, also the posterior unpaired interambulacrum : on the sides of the test they may be distinctly arranged in horizontal series. The primary spines curved at the base, directed backward, with a few distant serrations ; secondary spines curved. Tridentate, rostrate, and triphyllous pedicellariae present ; but none of the globiferous type. Ophicephalous pedicellariae found in the young of one species (paucituherculatus) . Color of test red, spines red or banded or yellowish. The denuded test white.

     Genotype : Eurypatagus ovalis, new species.

     The genus is nearly related to Maretia but differs from it in the open petals, the stronger development of the phyllodes, the greater posterior prolongation of the labrum, and the almost totally naked sternum. It is more nearly related to Platybrissus, from which it differs mainly in the character of the peristome.

Eurypatagus ovalis Mortensen,1948

EURYPATAGUS OVALIS, new species

     Locality.—Station 5217 (13°20' N., 123°14' E.) ; 192 meters; April 22, 1908. Five well-preserved specimens.
 

     Type.—U.S.N.M. No. E.7159, from station 5217.

     Description.—The largest specimen is 88 mm. long, 66 mm. broad, and 26 mm. high ; the smallest is 71 mm. long, 55 mm. broad, and 20 mm. high. The above description of the genus Eurypatagus applies equally to the species ovalis; a more detailed description therefore need not be given here. A full description, with illustrations, will be given in volume 5 of the Monograph of the Echinoidea. It may be stated here only that the tridentate pedicellariae occur in two forms, a large form, up to 1.5 mm. in length of head, with very slender, slightly curved valves, wide apart, meeting only at the point, and a smaller form with broader, spoon-shaped valves. The spines are to a varying degree red-brown with lighter bands.

Eurypatagus ovalis Mortensen,1948 - Actuel, Philippines, près de Caubian Island, 200 m, 74 mm