PROC. ENTOMOL. SOC. WASH. 106(2), 2004. pp. 475-477 Note Mealybug Species (Hemiptera: Pseudococcidae) Found on Ornamental Crops in California Nursery Production Mealybugs (Hemiptera: Pseudococcidae) are troublesome pests of ornamental crops throughout temperate regions of the world, including California. However, it is not cer-tain which mealybug species are most com-mon in California greenhouses and nurser-ies, and it is not known if recent, invasive species such as the pink hibiscus mealybug, Maconellicocciis hirsutus (Green), are pre-sent. Surveys and collections were made be-tween November 16, 2001 and March 7, 2003 to nurseries that reported mealybugs. Additionally, mealybugs were also sent di-rectly to the author by growers and advisors in University of California Cooperative Ex-tension. Mealybugs were collected or re-ceived from a total of 19 nurseries in five counties. The mealybugs were slide-mounted ac-cording to methods adopted from Kozar-zhevskaya (1968) and Williams and Gran-ara de Willink (1992). Slide-mounted mealybugs were identified using keys by McKenzie (1967) and an unpublished man-uscript by R. J. Gill. The mealybug species most frequently found in this survey of California green-houses were the longtailed mealybug, Pseu-dococcus longispinus (Targioni Tozzetti), and the citrus mealybug, Planococcus citri (Risso) (Table 1). With the exception of ro-ses, P. citri fed on many short-term crops such as coleus. whereas P. longispinus of-ten fed upon perennial crops such as cycad and Phonniiim tenax. The lilybulb mealy-bug, Vrybiirgia amaryllidis (Bouche), and the obscure mealybug, Pseudococcus vibur-ni (Signoret), were commonly found as well. Vryburgia amaryllidis is limited to a few plant families (especially Liliaceae and Iridaceae). It occurs on the bulb and on the basal portion of the leaves. Pseudococcus viburni was found both on the roots and the aerial portion of the plants, most commonly on short-term crops. Seven other mealybug species were found to occur less frequently. Many of these mealybugs were specialists found only on one species of plant. For example, the phormium mealybug, Balanococcus diminutus (Leonardi), is found only on Phormium tenax, and the noxious bamboo mealybug, Antonina pretiosa Ferris, is found only on bamboo species (Ben-Dov 1994). This survey allowed us to obtain a record of the mealybug species present in green-houses or nurseries in predominant growing areas of California. As growers are increas-ingly interested in incorporating natural en-emies into their insect control programs, in-formation on species composition is helpful for directing future biological control pro-jects. Thanks to K. Robb, S. Tjosvold and J. Newman (U.C. Cooperative Extension) for assisting with mealybug collections. We would also like to thank the University of California at Davis (arboretum and conser-vatory), Humbolt State University, Dramm and Echter Inc., Robert Hall Nursery, Gold-en State Bulb Co., Anderson Seed Co., Weidners' Gardens Inc., Aedes and Gish Nurseries, Browns' Plant Inc., Sea Coast Greenhouses, Suncrest Nurseries Inc., Ca-vanaugh Color. Kitayama Bros. Inc., Boe-thing Treeland Farms Inc., Sunshine Floral, Keeline Wilcox Nursery. McLellan Botan-icals, and Pajaro Valley Greenhouses Inc. for allowing the collection of mealybug specimens at their nurseries. Thank you to Ray Gill for allowing the use the manu-script; The Scale Insects of California: Part
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