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This note reports striking morphological aberrations of the compound eye, vertex and ocelli of a bee belonging to the genus Lasioglossum. Morphological aberrations of various kinds occur throughout the bees. Mitchell (1929), Michener (1943), Sivik (1962), Knerer and Atwood (1964), Wcislo et al. (2004), and Engel (2007) have reported sex anomalies, true gynandromorphs, antennal anomalies and metanotal anomalies. These reported aberrations primarily include changes in antennae, shape of the metasoma, genitalic structures, pollen collecting structures and the metanotum. Salt (1927) described the many external and internal changes in aculeate Hymenoptera caused by strepsipterous parasitism. Outside of Hymenopterans, Byers (1992) gave an account of distinct deformities of the head of a single individual of the scorpionfly Panorpa helena Byers, which had only a single normal compound eye and a single antenna both located on the right side of the head. However, no such dramatic aberrations of the head have previously been reported in bees. The ‘‘cyclops’’ bee described here, identified as a female of Lasioglossum (Dialictus) bruneri (Crawford), is therefore of some interest. I collected this unusual specimen on 13 July 2005 during a study conducted along roadsides in northeastern Kansas. The specimen was collected between the hours of 10:15 and 13:15 in a florescent yellow 16 oz. pan trap raised 70 cm above the ground, in the right-of-way along Highway 177 south of Cottonwood Falls in Chase County, Kansas. The most abundant forb in bloom in the area was Dalea purpurea Vent. (Fabaceae), with Ruellia humilis Nutt. (Acanthaceae), Dalea candida Michx. ex Willd. (Fabaceae), Amorpha canescens Pursh (Fabaceae) and Desmodium illinoense Gray (Fabaceae) present in smaller numbers. Land adjacent to the right-of-way was primarily rangeland grazed by cattle. Numerous Lasioglossum (Dialictus) spp. individuals were collected at this site prior to and after the collection of this specimen, although this individual was the only L. bruneri collected, and the only abnormal individual. The bee will be deposited in the Snow Entomological Collection, Division of Entomology, University of Kansas Natural History Museum, with the label J.L. Hopwood 2006 voucher. The bee has morphological aberrations of the head conspicuous enough to be seen without the aid of a microscope (Figs. 1–3). The size of the head is 75% of that of a typical specimen, with head width particularly reduced. Most readily noticeable is the fusion of the compound eyes at the vertex, which somewhat resembles the holoptic condition of honey bee drones and other insects such as syrphid flies, but instead results in a continuous, single compound eye (Fig. 1). This single compound eye extends completely over the vertex from either side of the head; thus a true vertex is lost and the ocelli are displaced. The remaining vertex is uniquely sculptured, with striations extending from the midline away from the occipital carina, along the gena (Fig. 2). The ocelli, normally located on the vertex, are situated on the frons just above the antennae. The sizes of the ocelli are highly reduced, as is the interocellar distance, and the ocelli are surrounded by an unusual and strong carina (Fig. 3). There are no other evident deformities of this individual. The mesosoma, wings, legs and metasoma are typical in appearance, with the exception of the presence of a female strepsipteran under the fourth tergum of the metasoma. While the morphological alterations of the head described above cannot definitively be attributed to stylopization, a noticeable decrease in head size has been described as an effect of stylopization (Salt, 1927). An extreme reduction in head size could account for the fusion of the compound eyes and the subsequent alteration of the vertex and ocelli. In any case, this individual has deformities 1 Current address: 33 Bessey Hall, Iowa State University, Ames, IA 50010, e-mail address |
