Very often I have come across species, of plant, animal and fungus, that upon searching the literature, reveal themselves to be actually a species complex, a number of species that are identical in many respects but are genetically distinct. The levels of these distinctions are often quite striking, as in the case of the Green Lacewing Chsysoperla carnea (Insecta: Neuroptera: Chrysopidae). This is a common insect of the summer months that is most recognisible from its almost ponderous flight and transparent, well veined wings. In the autumn time, the green adults hibernate, often indoors, their bodies turning a pinkish colour (1). The larvae feed on aphids and are used commercially to control aphid.
C. carnea has been shown to be a complex of many cryptic species, based on the songs they make to attract mates (2). When sexually receptive, members of the C. carnea group vibrate their abdomens, which in turn causes the substrate (generally a leaf) on which it stands to vibrate, generating a song. This process is known as tremulation. Both sexes tremulate, so only individuals with the same songs will be attracted to each other, and since song is genetically determined, this results in reproductive isolation of populations charactrerised by song. At least 15 groups within the C. carnea group have been described, differentiated by song (3).
As Neuropterans, lacewings are considered some of the oldest insects with complete metamorphosis (4). Ancient, extinct Neuropterans can be traced back to the Late Permian period, 260-251 million years ago. Of the current c. 6000 species of Neuropterans described, about 1200 belong to the family Chrysopidae, to which the C. carnea group belong.
- Sterry, 2004. Collins Complete Guide to Irish Wildlife p. 132
- Henry et al., 2002. Annals of the Entomological Society of America 95 pp. 172-191
- Henry et al., 1999. Evolution 53 pp. 1165-1179
- Tauber et al., 2009. Neuroptera in Encycolpedia of Insects, Resh and Cardé eds, pp. 695-707