GENERIC CORRELATIONS AND CONCEPTS: BROOMELLA AND PESTALOTIA

Abstract

The type and three additional species of Broomella from Clematis were treated as congeneric because of similar ascocarp structure, and because of the nature of the unitunicate asci, which, in all species, have a pulvillus (a subapical chitinoid body, "le coussinet chitinoïde"), but lack an iodine-reactive ring. Moreover, all the species have distinctive ascospores that are triseptate, pigmented only in the central cells, and furnished with one simple seta at each end. The conidia, like the ascospores, are four-celled with pigment only in the two central cells, but variously setose at the ends, and are produced on annellophores. Although two species have conidia with a single apical seta typical of Monochaetia, and two have multiple or branched setae typical of Pestalotia, the former generic dispositions of the conidial states made on numbers of setae and on fruit-body form were rejected and the conidial states united under one generic name, Pestalotia.Broomella vitalbae (Berk. & Broome) Sacc., the generic type, collected on Clematis vitalba L. in southern France, produced conidia with one simple seta at each end, and non-germinable microconidia (spermatia) when cultured. The conidial state is named Pestalotia vitalbae n. sp. North American collections of Broomella montaniensis (Ell. & Ev.) E. Müller & Ahmad on Clematis ligusticifolia Nutt. consistently bore the associated conidial state first described as Arthrobotryum pestalozzioides Dearness & Fairman in Fairman with which Pestalotia berberidis Guba was found to be conspecific. Pestalotia pestalozzioides (Dearness & Fairman in Fairman) n. comb. is proposed for the conidial state. Broomella excelsa collected in Pakistan on Clematis sp. and described as new was found in close association with the conidial state Ahmadinula excelsa Petrak for which Pestalotia excelsa (Petrak) n. comb. is proposed. Broomella acuta on Clematis flammula L. from southern France is described as new. Cultures from its ascospores and from conidia of Pestalotia truncata Lév. found on the same gathering, produced identical conidia, and, in addition, formed microconidia similar to those of Broomella vitalbae.