First Report of Arceuthobium hawksworthii in Honduras.

Abstract

The dwarf mistletoe Arceuthobium hawksworthii D. Wiens & C. G. Shaw (Viscaceae) has only been reported from the Mountain Pine Ridge area of Belize (1). We observed this dwarf mistletoe parasitizing its principal host, Caribbean pine (Pinus caribaea Morelet var. hondurensis (Senecl.) Barrett & Golf.) (1), 10 km east of Gualaco, Department Olancho, Honduras (elevation 800 m). Several trees were severely infected, and some dwarf mistletoe-associated mortality was observed at this location. The identification of A. hawksworthii was confirmed by comparing specimens collected from Honduras with specimens from Belize, which are deposited at the Deaver Herbarium, Northern Arizona University, Flagstaff. The mistletoes Psittacanthus angustifolius Kuijt and P. pinicola Kuijt (Loranthaceae) were also observed at this location parasitizing Caribbean pine. However, infection by both of these mistletoes was not severe, and no mistletoe-associated mortality was observed. Specimens of these mistletoes from Caribbean pine have been deposited at the Herbario, Escuela Nacional de Ciencias Forestales, Siguatepeque, Honduras. To our knowledge, this is the first report of A. hawksworthii from Honduras and extends its range approximately 350 km to the east-southeast of the Mountain Pine Ridge in Belize. This is also the first report P. angustifolius on Caribbean pine, but P. pinicola commonly infects this host in northern Honduras and Belize (2).