- Apical disc larger in diameter than peristomial opening; plating dicyclic.
- Ambulacra narrow, weakly sinuous. Pore-pairs narrow, non-conjugate, the two pores closely spaced in each pair.
- Ambulacral tuberculation uniform throughout; all plates simple.
- Perradial zone narrow with marginal tubercle and smaller inner tubercle to each plate.
- Interambulacral zones composed of 5-8 plates. Primary tubercles offset towards adradial suture. Oral and ambital tubercles imperforate, adapical tubercles may have a rudimentary perforation; all tubercles non-crenulate. Areoles sunken, with complete scrobicular circles. Extrascrobicular granules uniform and dense.
- Peristomial plating composed entirely of ambulacral elements; ambulacral plates biserially arranged in outer part.
- Spines claviform to glandiform with ribs or noded ornament.
Middle Jurassic (Bajocian) to Recent; Cretaceous of Europe, Palaeocene of Europe, central Asia, the Caribbean and North America, Miocene of Sardinia, Recent of Japan.
Cidaris clavigera Mantell, 1822, p. 194, by subsequent designation of Lambert & Thiery, 1910, p. 156.
- T. honorinae Cotteau, 1880; Bajocian-Bathonian, Europe.
- T. propinquus (Munster, in Goldfuss, 1829); Oxfordian, Europe.
- T. (Tylocidaris) velifera (Agassiz & Desor, 1846): Upper Albian to Cenomanian, western Europe.
- T. (Tylocidaris) sorigneti (Desor, 1856); Uppermost Cenomanian and Lower Turonian, Europe.
- T. (Tylocidaris) clavigera (Mantell, 1822); Upper Turonian to Upper Santonian, Europe.
- T. (Tylocidaris) gosae Schlueter, 1892; Campanian, Europe.
- T. (Tylocidaris) vexillifera (Schlueter, 1892); Danian, NW Europe.
- T. (Tylocidaris) inexspectata Jagt & van der Ham, 1995; Maastrichtian, The Netherlands.
- T. (Tylocidaris) hardouini (Desor, 1855); Danian, Europe, Ukraine, South USA.
- T. sp. [T. walcotti Clark, 1915]; Thanetian, Eastern USA.
- T. hemmoorensis Salah & Schmid, 1982; Maastrichtian, Germany.
- T. (Oedematocidaris) asperula (Roemer, 1841); Cenomanian, Europe.
- T. (Oedematocidaris) pleracantha (Agassiz & Desor, 1846); Santonian-Campanian, Europe.
- T. (Oedematocidaris) baltica (Schlueter, 1892); Maastrichtian, Europe.
- T. (Sardocidaris) ramondi (Leymerie, 1851); Maastrichtian, Spain; Lower Palaeocene, Kopet Dag.
- T. (Sardocidaris) piae (Lambert, 1907); Miocene, Sardinia.
- T. (Psychocidaris) ohshimai (Ikeda, 1935); Recent, Japan.
|Classification and/or Status
T. (Oedoematocidaris) was established as a subgenus for forms with glandiform spines in which the cortical stereom hairs are dense and form a fused secondary overgrowth. Psychocidaris was established for the Recent species oshimai by Ikeda, who was unaware of the existence of the fossil Tylocidaris. It is here treated as a subgenus for forms with strongly flanged adoral spines. Sardocidaris is here treated as another subgenus for forms with rather elongate subambital spines with a pustular ornament. Tylocidaris (Tylocidaris) is restricted to forms whose spines are ornamented with beaded ribs or rows of small thorns.
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.
Pomel, A. 1883. Classification methodique et genera des echinides vivants et fossils. Thesis presentees a la Faculte des Sciences, Paris. A. Jourdan, Alger, 131 pp.