Balaustium spp. In Florida

The cosmopolitan genus Balaustium was first described from Europe in 1826. Since then approximately 20 species have been described, mostly from the northern hemisphere. Four species are currently recognized in North America: B. aonidophagus (Ebeling), B. dowelli Smiley, B. kendalli Welbourn and B. putmani Smiley, but additional species remain undescribed. Balaustium is a predator of small insects and mites (Welbourn 1983 and references therein). One species, B. putmani, has been studied as a possible biological control agent in orchards (Putman 1970; Cadogan and Laing 1977; Childers and Rock 1981).

Balaustium spp. are commonly found in urban areas, where they appear in large numbers on sidewalks and walls for a brief period during the spring and early summer. It is during this time that they sometimes enter homes and buildings and become pests. There are two records of Balaustium spp. from Florida homes (FSCA collection). Newell (1963) reported four cases of Balaustium spp. biting humans; of these, three involved mites that had invaded buildings.

Balaustium putmani is known from orchards in Ontario, Canada (Putman 1970; Cadogan and Laing 1977) and North Carolina (Childers and Rock 1981 ), while B. dowelli is known only from Arkansas (Smiley 1964). Balaustium aonidophagus (Ebeling) is known only from southern California (Ebeling 1934), and B. kendalli is reported from Maine (Welbourn and Jennings 1991). Balaustium spp. have also been reported in the literature from California (Struble 1972), Colorado (Hays 1985) and Montana (Fellin 1968). There are at least two undescribed species in Florida.