Vol. 106, No.3, May & June, 1995 97 DIVERSITY AND PHENOLOGY OF TUMBLING FLOWER BEETLES (COLEOPTERA: MORDELLIDAE) CAPTURED IN A MALAISE TRAP 1 J. A. Jackman 2 , C. R. Nelson 3 ABSTRACT: Adult mordellid beetles were monitored at Brackenridge Field Laboratory in Austin, Texas from January 1990 through December 1990 using a Malaise trap. A total of 754 specimens representing 35 species (17% of the North American fauna) and one subspecies were taken in this study. Twenty-eight of the species and one subspecies are recorded for the first time from Texas. Specimens were collected as early as March 13-19 and as late as November 27-December 3. Up to 19 species, nearly 10% of the mordellid fauna of North American north of Mexico, were collected in a single week. However, 19 (52%) of the taxa reported in this study were represented by five or fewer specimens indicating that most species were relatively rare. The seasonal flight pattern indicated a unimodal flight activity pattern for the family and also for most species. The Brackenridge Field Laboratory (BFL). located in Austin, Texas, is operated by the University of Texas at Austin and consists of approximately 50 hectares (80 acres) of land which has been used for a variety of purposes during its recent history. For the past 25 years the land comprising BFL has been a preserve and field laboratory used by researchers and students for var-ious ecological and behavioral studies, e.g., Porter and Savignano (1990). BFL, with its juxtaposition of relatively undisturbed and disturbed areas pre-sents an interesting mosaic of plant species available to various herbivores, such as tumbling flower beetles (Mordellidae). Ongoing studies of the diver-sity of insect species present at BFL are being conducted by researchers there. A goal of these studies is a more complete knowledge of the entire insect com-munity at a single site in the ecologically rich central Texas area. This study of mordellid beetles complements extensive surveys of other taxa, such as dig-ger wasps (Sphecidae), moths, robber flies (Asilidae), bees, ants, leaf-footed bugs and Odonata. This survey also intends to spur interest in other re-searchers so that comparisons of similar communities in different ecoregions and biotic provinces can be made. An ancillary goal of this study is to provide researchers in central Texas with an indication of groups of particular ecolog-ical concern. For instance, the rich assemblage of mordellid beetles brought to light during this study could be the impetus for additional work of general ecological interest in addressing questions of competition, niche sep-1 Received November 17, 1994. Accepted December 13. 1994 2 Professor and Extension Entomology Specialist, Texas A&M University, College Station, Texas 77843-2475. 3 Division of Biological Science and Brackenridge Field Laboratory, University of Texas at Austin, Texas 787 12. ENT. NEWS 106(3): 97-107, May & June. 1995
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