Synonyms and other taxonomic changes
Draeculacephala sphagneticola (Hamilton, 1985)
Draeculacephala zeae (Hamilton, 1985)
Explanation of Names
Draeculacephala robinsoni (Hamilton, 1967)
Size
♂♂ 6.5-8.2mm, ♀♀ 8.0-10.5mm
Identification
A green species with (almost always) blue venation, usually having a dark face. The abdominal sterna are described as being pale/yellow, but there is a high degree of variation among individuals (some can be very dark brown with yellow parts). Females can have dark faces, but males are usually darker as a whole on the underside. This species mainly differs from the similar D. mollipes based on size, coupled with the colour of the face. D. mollipes usually has a yellow face, though it can sometimes be brown to the point of overlap with the morphology of robinsoni, so it's quite important to get lateral and ventral photos coupled with a measurement.
Range
widespread throughout the U.S. and Canada east of Rocky Mts.; populations in western Canada and Washington (Hamilton, 1985), though these individuals seem to have paler venation
Habitat
grasslands, lawns, fields, etc.; also found in somewhat specialised habitats
Remarks
One of (if not the) most common members of the genus.
The status of Draeculacephala zeae has been under debate—Dietrich's taxonomy is followed here:
"The 2S and 3S apodemes are highly variable in shape among individuals of D. robinsoni based on slight differences in the shape of the 2S apodemes. His division, between those individuals having the lower half of the apodeme produced more strongly and those having the upper have more produced, seems arbitrary, and, although possibly correlated with body length (Hamilton, 1985), is not supported by other morphological characters. Without additional evidence to suggest that these groups represent distinct species, I consider them synonyms."
Hamilton & Chandler (2017) disputed this based on genetic barcoding, reinstating the species under the statement that zeae specimens cluster separately from those of robinsoni. This opens up the possibility that this species is actually a complex and there is the possibility of intergradation.
See Also
Draeculacephala mollipes — a blue-veined species that can be morphologically quite similar.
Draeculacephala producta — a similar sister species with a much more protruding head and darker abdominal sterna, confined to the Gulf states.
Draeculacephala paludosa — this is a morphologically similar species with darker markings, occurring in the Great Lakes region
