Triphyllopteris collombiana: A Clarification of the Generic Concept Based on Rediscovered Specimens from Kossberg BEI Plauen, Germany, and a Reassignment of the North American Species of Triphyllopteris to Genselia gen. nov.
1994; University of Chicago Press; Volume: 155; Issue: 1 Linguagem: Inglês
10.1086/297151
ISSN1537-5315
Autores Tópico(s)Fern and Epiphyte Biology
ResumoA whole frond reconstruction of Triphyllopteris collombiana Schimper is presented based on specimens from Kossberg bei Plauen, Saxony, Germany. New information is derived from fragments of a frond apex, a basal portion of the rachis, and a medial fragment that demonstrate the transition in pinnule shapes from base to apex. Because Schimper's original material was lost in a fire without being refigured, and because this material clearly exhibits a spatial arrangement of pinnule shape variation that conforms precisely to Schimper's diagnosis, I have designated the largest of the Kossberg specimens as a neotype. An emended generic diagnosis clarifies the overall frond shape and architecture and defines precisely the range and spatial pattern to pinnule shape variation. With this clarification of the intent of Schimper's original diagnosis, it is now possible to assess whether specimens that subsequent workers have assigned to Triphyllopteris do in fact conform to Schimper's original concept of the genus. Specimens from the Appalachian Basin of North America do not conform to either Schimper's original diagnosis or the emended generic diagnosis. The North American material is reassigned to Genselia gen. nov. It is now clear that T. collombiana was an unusual and perhaps fairly rare plant, confined in its geographic range to central Europe and Spain, and that the several species of Genselia were confined to the Appalachian Basin of North American.
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