Explanation of Names
Graphocephala coccinea (Forster 1771)
Numbers
2 subspecies described, though not universally accepted
Size
G. c. coccinea: ♂ 5.7‒6.2 mm, ♀ 6.7‒7.3 mm; G. c. quadrivittata: ♂ 6.6‒7.6 mm, ♀ 7.2‒8.4 mm; G. c. var. teliformis (no taxonomic status): ♂ 7.2‒8.5mm, ♀ 8.0‒9.1mm
Identification
variable, can be confused with similar species throughout its range. It is generally a bright blue to green species with two to three bright red stripes across the forewings and on the pronotum that vary in boldness. The scutellum is generally orange with the head and underside of the body being a pale to bright yellow. A bold black stripe stretches around the top of the face, to and past the eyes. In very bold specimens, the top of the head may have orange or red pigmentation and the dark markings at the top of the face may extend throughout the entire face and even reach the top of the head in a bold outline (this is most often seen in the coastal subspecies G. c. coccinea). Nymphs of this species cannot be distinguished from those of others in this genus without rearing or association with an adult. They are a pale white to cream colour with yellow edges, eventually developing red stripes dorsally and becoming deeper yellow in later instars.
Varying morphs suggest that there may be cryptic species.
Range
e. Canada (QC‒SK) to Panama
(1)(2);
G. c. coccinea Atlantic Coast,
G. c. quadrivittata inland
Remarks
It has been suggested that this is likely a species complex with possibly intergrading species—synonymies and reinstations of species have been quite common among this group. Some authors treat G. idonea (Mexican to Central American), G. picta (northeastern U.S.), and G. teliformis (eastern U.S.) as distinct species, but most consider them synonyms of G. coccinea due to these forms currently being poorly or dubiously defined. G. idonea in itself may represent a neotropical species complex due to very diverse forms being seen (which seem to be geographically isolated from one another). The subspecies G. c. quadrivittata and G. c. coccinea are also often treated as synonyms, but since they are more easily defined from a morphological standpoint, we have retained them on BugGuide for now.
G. c. coccinea is a coastal subspecies found on the Atlantic coast and various coastal islands—it is usually a much bolder and smaller subspecies with the red markings being bolder than the underlying blue ones. G. c. quadrivittata is the inland subspecies which is much larger and usually well-marked, but not as bold.
This species can be notoriously difficult to differentiate from the similar species Graphocephala fennahi and Graphocephala constricta. G. fennahi, the Rhododendron Leafhopper, seems to feed exclusively on Rhododendron and has faint markings, almost always lacking the third red stripe on the forewings (usually with a green base, but sometimes a pale blue). It has a smaller native range than G. coccinea (it's not found in the deep south), though it has been introduced to the Pacific Northwest and throughout Europe (where G. coccinea are not present), likely through horticultural trade. It is important to obtain measurements for this species as northeastern members of G. coccinea (such as the form "picta") can look nearly identical. It is widely accepted that G. fennahi is clearly distinct from the rest of G. coccinea.
Graphocephala constricta is a central U.S. and Texan species, falling right on the western edge of the southern range of G. coccinea. Its appearance is practically identical to that of the most common forms of G. coccinea, but it is significantly smaller. While the source BugGuide uses for hopper taxonomy (3i) treats G. constricta as a valid species, some authors agree that it likely should be treated in the same respect as the forms teliformis and picta due to insufficient evidence towards its distinction from the rest of the coccinea complex. G. constricta usually has red pigmentation on the top of the head, a trait uncommon in coccinea, but present.
This species may turn out to be a group of distinct species, or of intergrading species, or a single highly variable species. Molecular work or analysis of courtship calls may clarify matters.
