Cole et al.—Camerates from an Upper Ordovician Lagerstätte, Ontario
followed by four to six higher rows each with three to six irregularly organized plates that decrease in size distally and grade into the tegmen. Posterior interray undifferentiated or not observed. First primibrachial fixed, hexagonal, more than twice as
wide as high; second primibrachial axillary, pentagonal. Secundibrachials two, fixed, second secundibrachial axillary. Fixed tertibrachials usually giving rise abaxially to one fixed pinnule in each quarter ray, fixed pinnule placement variable, arms typically free above fourth tertibrachial. Fixed intrabra- chials between secundibrachials and tertibrachials of each half ray, proximal plating 1-2-2, no fixed intrabrachials between quarter rays. Arm openings 20, grouped by half rays, with robust arm
bases protruding from the calyx. Free arms unbranched, tapering gradually, pinnulate; brachials wedge biserial through- out free arms. Tegmen conical, nearly as high as calyx; tegmen plates
thick, polygonal, similar in size and ornamentation to distal interray plates. Anal opening unknown. Stem circular, holomeric; heteromorphic N212 in proximal and medial stem. Distal stem, holdfast, and lumen unknown.
Etymology.—The specific name is after the Latin elegans, meaning elegant or graceful.
Materials.—UMMP 74678.1, holotype; 74678.2, paratype; 74679, paratype; 74680, paratype (Bobcaygeon-Verulam contact zone, LaFarge Quarry).
Remarks.—It does not appear that this or any other species of Priscillacrinus n. gen. was previously recognized from material collected from the Kirkfield region. It is one of the rarest species in the collection described herein, yet is distinctive because of its heavy ornamentation on the calyx plates.
Family Cleiocrinidae Miller, 1890 Genus Cleiocrinus Billings, 1857
Type species.—Cleiocrinus regius Billings, 1857.
Diagnosis.—Calyx high conical or pyriform; calyx plates per- forated by many pores along plate sutures; infrabasals in deeply invaginated basal concavity; basals and radials five each, in a single circlet of 10 plates that overlaps the stem and basal con- cavity; fixed brachials bifurcating asymmetrically numerous times within the calyx, giving rise to 40 or more arms and fixed ramules; interray plates absent, brachial plates sutured together; CD interray comprised of a single column of plates.
Occurrence.—Middle–Upper Ordovician (Darriwilian–Katian); United States (Oklahoma, New York, Iowa, Tennessee, Kentucky) and Canada (Ontario).
Remarks.—After contemplating the phylogenetic position of Cleiocrinus, Frank Springer (1911, p. 44) concluded, “…until better proofs of its relations are furnished it will have to remain in a sort of palaeontological no-man’sland.” Indeed, Cleiocrinus is a bizarre taxon unlike any other crinoid known, and its affinities
497
with other taxa remain obscure. Originally, the genus was thought to have diverged from other diplobathrids early in the evolutionary history of camerates, and Cleiocrinus was assigned along with Spyridocrinus to suborder Zygodiplobathrina, where- as all other diplobathrids were assigned to Eudiplobathrina (Ubaghs, 1953, 1978). However, this superordinal division has not been supported by phylogenetic analysis (Cole, 2017). Despite its many unusual apomorphic features, Cleiocrinus is well known and moderately diverse (see Springer, 1905; Guensburg, 1984).
Cleiocrinus regius Billings, 1857 Figure 4.5
Holotype.—GSC 1443a.
1857 Cleiocrinus regius Billings, p. 276. 1859 Cleiocrinus regius; Billings, p. 53, pl. 5, figs. 1a–g. 1868 Cleiocrinus regius; Shumard, p. 359. 1868 Cleiocrinus regius; Bigsby, p. 18. 1889 Cleiocrinus regius; Miller, p. 232, fig. 264. 1905 Cleiocrinus regius; Springer, p. 110, pl. 1, figs. 1–10. 1910 Cleiocrinus regius; Grabau and Shimer, p. 562. 1911 Cleiocrinus regius; Springer, p. 41, pl. 5, figs. 7–9. 1915 Cleiocrinus regius; Bassler, p. 230. 1938 Cleiocrinus regius; Bassler, p. 67. 1943 Cleiocrinus regius; Bassler and Moodey, p. 365. 1946 Cleiocrinus regius; Wilson, p. 23, pl. 5, fig. 2. 1950 Cleiocrinus regius; Ubaghs, p. 119, fig. 7. 1953 Cleiocrinus regius; Ubaghs, figs. 33d–f. 1973 Cleiocrinus regius; Webster, p. 81. 1978a Cleiocrinus regius; Ubaghs in Moore and Teichert, p. T102, figs. 76.1, 174.1–3, 221.1a–d.
1986 Cleiocrinus regius; Webster, p. 97. 1994 Cleiocrinus regius; Brower, p. 570, fig. 1.
1999 Cleiocrinus regius; Simms in Hess et al., p. 32, figs. 54a, 54b.
Diagnosis.—Cleiocrinus with an elongate calyx; distinct, narrow median ray ridges; plates ornamented with fine ridges crossing plate sutures; pores positioned along plate sutures, ~18 pores per 5mm; two primibrachials, three to seven secundibra- chials, four to twelve tertibrachials.
Occurrence.—Cleiocrinus regiuswas previously known fromthe Upper Ordovician (Katian)Hull and Cobourg formations, Ottawa Group, Ontario and from the Upper Ordovician (Katian) Rivoli Member of the Dunleith Formation, Galena Group, Iowa. The occurrence documented here is from the Bobcaygeon-Verulam contact zone, LaFarge Quarry, Upper Ordovician (lower Katian).
Materials.—UMMP 74681.1 (Bobcaygeon-Verulam contact zone, LaFarge Quarry); USNM S7137 (middle–upper Bobcaygeon Formation, Kirkfield Quarry).
Remarks.—Extensive material is known for C. regius, and the species was described at length by Springer (1905).
Cleiocrinus lepidotus new species Figure 6.1–6.11
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