Golding and Orchard—A new conodont genus from the Triassic of North America
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Figure 2. Maps showing the geographic locations of samples collected from Nevada and B.C. Collections were primarily obtained from samples of
limestone or calcareous siltstone, often taken from the same horizon as ammonoid samples. All of the conodont samples were previously processed at the Geological Survey of Canada in Vancouver, using standard techniques as outlined in Stone (1987) and Jeppsson et al. (1999).
Repository and institutional abbreviation.—Illustrated speci- mens are housed at the National Type Collection of Invertebrate and Plant Fossils at the Geological Survey of Canada (GSC) in Ottawa, Ontario, Canada.
Systematic paleontology
Class Conodonta Pander, 1856 Order Ozarkodinida Dzik, 1976
Family Gondolellidae Lindström, 1970 Subfamily Neogondolellinae Hirsch, 1994
Genus Magnigondolella new genus Figure 3
Type Species.—Magnigondolella salomae n. gen. n. sp.
Other species.—Neogondolella regalis Mosher; Neogondolella dilacerata Golding and Orchard; Neogondolella sp. sensu Orchard et al. (2007a); Neogondolella sp. sensu Orchard et al. (2007b); Magnigondolella alexanderi n. gen. n. sp.; Magnigondolella cyri n. gen. n. sp.; Magnigondolella julii n. gen. n. sp.; Magnigondolella nebuchadnezzari n. gen. n. sp.; Magnigondolella salomae n. gen. n. sp.; Magnigondolella n.
gen. n. sp. A; Magnigondolella n. gen. n. sp. B; and Magnigondolella n. gen. n. sp. C.
Diagnosis.—Genus with a 15-element apparatus including a P1 element that is segminiplanate, with a high, fused carina of uniform height; and an S0 element that is alate, with lateral processes that diverge from the cusp.
Description.—The diagnostic P1 element is segminiplanate, with a biconvex platform that is widest at, or posterior to the midpoint of the element. A posterior platform brim may be present. Micro-reticulation is present on the margins of the platform. In side view, the element is arched, and the platform margins are upturned. The carina is high and uniformly well fused along its length. The upper margin of the carina is straight for most of its length, but may be deflected downward at the posterior end due to the curvature of the element. The denticles of the carina are laterally compressed and vary from upright to slightly inclined. The sub-terminal cusp is similar in size to, or slightly larger than the adjacent denticles, and a posterior denticle is present at all growth stages. On the lower surface, a relatively low keel of variable width is present, which terminates in a round to sub-quadrate loop around the sub-terminal basal pit.
Comparisons.—The uniformly high, fused carina of the P1 element distinguishes Magnigondolella n. gen. from Neogondolella, which has a P1 element with a much lower carina that rises to the anterior and posterior of the element. P1 elements of Paragondolella have a high and fused carina like that of Magnigondolella n. gen., but it forms a convex crest that is highest in the midpoint of the element, descending to both the anterior and posterior. The upper profile of the carina places
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