Vol. 89, Nos. 7 & 8, September & October 1978 153 BRACHYNEMURUS NEBULOSVS (NEUROPTERA: MYRMELEONTIDAE): A POSSIBLE BATESIAN MIMIC OF FLORIDA MUTILLID WASPS (HYMENOPTERA: MUTILLID AE)i Vincent Brach ABSTRACT: Laiva.1 Brachynemurus nebulosus (Neuroptera: Myrmeleontidae) from Flor-ida exhibit a bold color pattern of orange-red, white and black which resembles that of three sympatric species of mutillid wasps (Mutillidae). When uncovered, B. nebulosus larvae run over the substrate in zig-zag dashes, further increasing their resemblance to mutillid wasps. It is suggested that the atypical coloration and behavior of fl. nebulosus larvae may constitute a generalized Batesian mimicry of at least three of the common species of Dasymutilla of the region. Mutillid wasps, or "velvet ants", are common and conspicuous inhabitants of open, sandy areas throughout the United States. Most display prominent aposematic patterns of red, orange, or yellow and black which often include whitish rings at the tip of the abdomen. This bold coloration and the rapid, zig-zag locomotion characteristic of the wingless females serves as a fair warning to would-be predators of the heavily armored bodies and formidable stings of these insects, the effect of the latter having been likened to a strong electric shock. While collecting mutillid wasps at the Archbold Biological Station, High-lands Co., Florida, during the spring and summer of 1976, a visiting graduate student collected two specimens of larval antlions which bore a striking be-havioral and morphological resemblance to mutillid wasps when viewed from above (Fig. 1). One of these larvae was reared and the imago identified as Brachynemums nebulosus (Oliv.). The color of the head, thorax and anterior abdomen of these larvae in life is bright red dish -orange, while tlie latter half of the abdomen is boldly marked in black and white. In alcohol, the reddish-orange fades somewhat, but is still quite different from the dull brown and gray color of all other known larvae of Brachyneinunis (Stange, 1970). The behavior of the two B. nebulosus larvae was unusual in that the larvae would frequently run in abrupt dashes on top of the sand, rather than spending all of their time beneath it as do all other known Brachynemums larvae. If buried B. nebulosus larvae were suddenly unearthed, they would often begin to run instead of lying motionless in the manner of cryptically-colored myrmeleontid larvae. This atypical behavior increases the resem-blance of B. nebulosus larvae to mutillid wasps; indeed, both of the larval Accepted for publication: June 26, 1978 2 Department of Biology, Texas Eastern University, Tyler, Texas 75701 ENT. NEWS, 89: 7 & 8: 153 -156, September & October 1978
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