Eucommiitheca hirsuta, a new pollen organ withEucommiiditespollen from the Early Cretaceous of Portugal

Abstract

Abstract A new pollen organ, Eucommiitheca hirsuta, containing Eucommiidites pollen grains is described from the Early Cretaceous of Portugal. The material comprises dispersed microsporangiate units and fragments of axes bearing microsporangiate units in an opposite and decussate arrangement. Each microsporangiate unit consists of a slightly angular to rounded peltate scale attached centrally to a short stalk, and with whorls of sporangia around the distal part of the stalk. Sporangia are stalked and free, with longitudinal dehiscence, and contain pollen grains similar to the characteristic dispersed pollen genus Eucommiidites. Eucommiitheca is comparable to Erdtmanitheca, another Cretaceous pollen organ containing Eucommiidites pollen, in the peltate nature of the microsporangiate units, but microsporangiate units in Erdtmanitheca are arranged in dense heads and sporangia are elongate. The opposite and decussate arrangement of the microsporangiate units in Eucommiitheca is in accordance with the possible...