Cephalopoda - Ammonitida - Ataxioceratidae
Description: Inner whorl with rather distant bifurcate ribs. Penultimate whorl in the beginning still bifurcate ribbed, then 3-4 secondaries. On the outer whorl transition to bifur- cate ribs with one or two intercalatories. Larger specimens loose the intercalatories as the diameter increases and then only exhibit very strong single or highly branched bifurcate ribs. The branching points on the inner and penultimate whorls lie in the middle or in the upper two thirds of the flanks. Specimens belonging to this species are very com- mon in the Los Catutos and El Ministerio quarries (PI. 36/1).
Full reference: H. Leanza, A. Zeiss, A. Cione, W.C. Dullo, E. Flugel, J.I. Carate-Zubillaga, and Z. Gasparini. 1990. Upper Jurassic Lithographic Limestones from Argentina (Neuquen Basin): Stratigraphy and Fossils. Facies 22:169-186
Parent taxon: Zapaliinae according to H. Parent et al. 2017
See also Leanza et al. 1990
Sister taxa: Choicensisphinctes, Indansites, Krantziceras, Platydiscus
Subtaxa: Zapalia fascipartita
Ecology: fast-moving nektonic carnivore
Distribution:
• Jurassic of Argentina (3 collections)
Total: 3 collections including 6 occurrences
Specimen images are retrieved through the ePANDDA API.
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