ABSTRACT: Flajsella is a genus based on the Paelements of a small, distinctive, highly variable conodont that had a cosmopolitan distribution during the middle Lochkovian (Early Devonian). Several suggestions have been made with respect to the composition of its apparatus and five of its elements were figured as 'Apparatus A' by Mastandrea (1985) from Sardinia but are not connected to Flajsella. Two samples from the Tor Limestone and additional samples from the McMonnigal Limestone in the Toquima Range, central Nevada, provide the basis for the following hypothesis for a complete reconstruction of its skeletal apparatus. Flajsella has a seximembrate apparatus of small, delicate elements with narrow, closely packed, irregular denticles on high, thin bladeswith extensions of white matter into the blade from the base of the denticle.One or both of the processes of the Pb, Sa, Sb, and Sc elements may be bent inward. The posterior blade in the Melement is long and nearly straight, with erect, appressed, parallel-sided denticles, nearly parallel to the cusp. The basal cavity in the Sa element is narrow and turned to the posterior. The Sb element is similar but skewed. The Sc element has a relatively long, arched posterior blade and a short, expanded anterior blade that is sharply turned down immediately behind the cusp. Contrary to the Pa element, the cavities of the Sa and Sb elements are very small, whereas, in the Mand Sc elements the basal cavities are more expanded under the processes. This reconstruction is supported by samples from Sardinia, Alaska, and other localities in Nevada. An occurrence in the McMonnigal Limestone enlarges the distribution of two of its species, Flajsella schulzei and F. sigmostygia, and supports previous data regarding a stratigraphic position in the highest part of the middle Lochkovian because of the co-occurrence with Kimognathus delta, Ancyrodelloides transitans, Lanea eleanorae, and Amydrotaxis praejohnsoni, an assemblage indicative of the eleanorae-trigonicus Zone of Valenzuela-Rios and Murphy (1997) in Nevada.
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