Paraconocrinus, Roux & Eléaume & Améziane, 2019

Roux, Michel, Eléaume, Marc & Améziane, Nadia, 2019, A revision of the genus Conocrinus d’Orbigny, 1850 (Echinodermata, Crinoidea, Rhizocrinidae) and its place among extant and fossil crinoids with a xenomorphic stalk, Zootaxa 4560 (1), pp. 51-84 : 78

Genus Paraconocrinus n. gen.

Type species. Eugeniacrinus pyriformis Münster in Goldfuss, 1826 .

Diagnosis. Theca devoid of proximale, aboral cup subhemispherical to inverted conical, or moderately elongated; distal radial circlet with crescentic to oval articular facets separated by short thick ribs, never interradial process or thorn, muscular synarthry of deep muscular fossae without inner turn up, ratio arm socket to radial width 0.60 to 0.90, ratio central depression to distal cup diameter 0.55 to 0.60, wall of central depression formed by five conspicuous interradial units without suture and separated by radial grooves; short IBr1 with distal facet convex and smooth (synostosis), occasionally preserved between interradial ribs; columnal synarthries in distal mesistele and dististele with slight depression accentuating fulcral ridge relief in addition to figure 8-shaped ligament fossa; arms unknown.

Included species. Eugeniacrinus pyriformis (Priabonian) ; Conocrinus cazioti Valette, 1924 (Bartonian) ; C. handiaensis Roux, 1978 (Bartonian) ; C. romanensis Roux and Plaziat, 1978 (late Ypresian); P. pellati n. sp. (Bartonian).

Remarks. The first illustration of a distal aboral cup of the Paraconocrinus type is that of Eugeniacrinus pyriformis from northeast Italy (Münster in Goldfuss 1826: pl. 60, fig. 6). Subsequently, too many Eocene cups of various morphologies were lumped with this species. For example, Manni (2005) proposed that P. handiaensis was a junior synonym of P. pyriformis . The Bartonian species P. cazioti and P. handiaensis seem to be very closely related, but new Priabonian material from southeast France and northeast Italy suggests that P. pyriformis is a small species that is clearly different from the other two (Roux et al. in prep.).