Leonispirifer leonensis gen. et sp. nov., a rare new delthyridoid spiriferid brachiopod from northern Spain (Brachiopoda, Lower Devonian)

Abstract

Leonispirifer, a new delthyridoid brachiopod genus characterized by capillate micro-ornamentation with marginal microspines, very few ribs, and a brachidium consisting of spirals that have a small diameter and are oriented in the posterior direction, is identified from the Emsian La Vid Group in its type section in the Cantabrian Mountains in northern Spain. Its type species Leonispirifer leonensis is described and its phylogenetic origin from Filispirifer is discussed. For the first time, 3D reconstructions of Filispirifer and Leonispirifer are prepared that show the different spiralia orientations, lateral versus posterior, of these two genera. An attempt is made to reconstruct the life habits of Leonispirifer, paying special attention to its lophophore-based filter-feeding system. Leonispirifer was hitherto known from the Emsian La Pedrosa Formation of the La Vid Group in northern Spain, and probably from the Siegenian Assa Formation (“Rich 1”) in Morocco. According to Early Devonian paleobiogeography, both regions belonged to the northern shelf of Gondwana.