The Echinoid Directory

Phalacrocidaris Lambert, 1902, p. 26

[=Anomocidaris Agassiz & Clark, 1907, p. 30, type species Cidaris tenuispinus Yoshiwara, 1898 (=Dorocidaris japonica Doderlein, 1885)]

Diagnostic Features	Test relatively thick-shelled and subconical in profile. Apical disc slightly raised; about 50% test diameter; plating dicyclic, with relatively small periproctal area. Genital plate 2 slightly larger than the others. Interambulacra with 6-9 plates in a series. Primary tubercles perforate and non-crenulate; areoles incised and non-confluent. Upper two or three plates in each column with only rudimentary primary tubercles. Scrobicular tubercles weakly differentiated. Extrascrobicular zones densely and uniformly covered in secondary tubercles, often with neural grooves. Weak pits or incised sutures in adoral parts of interambulacral zones only. Ambulacra more or less straight. Pore zones not much incised; pore-pairs small and non-conjugate. Interporal zone narrow with marginal primary and smaller secondary tubercle per plate. Peristome smaller than apical disc. Interradial plates not reaching the mouth; ambulacral plates uniserial in each column. Primary spines long, slender and cylindrical. Collar short and shaft ornamented with fine serrated ribs. Secondary spines not adpressed.
Distribution	Upper Cretaceous (Cenomanian) to Recent, Europe, Australia, Indo-Pacific.
Name gender	feminine
Type	Dorocidaris japonica Doderlein, 1885, p. 4, by original designation.
Species Included	P. vesiculosa (Goldfuss, 1829); Cenomanian, Europe. P. serrifera (Forbes, 1850); Turonian, Europe. P. merceyi (Cotteau, 1862); Upper Coniacian-Lower Santonian, Europe. P. catherinae Smith & Wright 1989; Campanian, UK. P. inermis Philip, 1965; Eocene, Australia. P. japonica Doderlein, 1885; Recent, Japan.
Classification and/or Status	Cidaroida; Cidaridae; Stereocidarinae. ?Monophyletic.
Remarks	Distinguished from Stereocidaris by having aboral interambulacral plates bearing rudimentary primary tubercles which are not markedly elongate vertically, and by its simple cylindrical spines. Lambert, J. 1902. Description des echinides fossiles de la province de Barcelone. Memoires de la Societe geologique de France, Paleontologie 9, 1-58, 4 pls. Smith, A. B. & Wright, C. W. 1989. British Cretaceous echinoids. Part 1, General introduction and Cidaroida. Monograph of the Palaeontographical Society [publication no. 578, issued as part of volume 141] p. 1-101, pls 1-32. Mortensen, T. 1928. A monograph of the Echinoidea. 1, Cidaroidea. C. A. Reitzel, Copenhagen.