Explanation of Names
Graphocephala (Van Duzee, 1916)
19 described spp. in our area
NOTE: the notation citing the taxonomic authority of the listed species may have been inputted erroneously. This is pending correction.
Graphocephala “species group”
(Forster, J.R., 1771): Eastern U.S.; introduced in Utah and other regions of the western U.S.
: (Hamilton, 1985): TX, OK [likely a synonym of coccinea
(Young, 1977): Eastern U.S., introduced in PNW and Europe
(Say, 1830): Eastern U.S., introduced in southwestern U.S. and Mexico
Hordnia “species group”
(Signoret, 1854): Western U.S.
(Baker, 1898): AZ, Mexico
(Baker, 1898): SW U.S., Mexico
(Ball, 1936): AZ, Mexico
Marathonia "species group"
Graphocephala marathonensis (Ball, 1936): TX, Mexico
Neokolla/Keonolla "species group"
(Uhler, 1861): Western U.S.
(Signoret, 1854): SW U.S. and CO
(DeLong & Currie, 1960): AZ and Mexico
(DeLong & Currie, 1960): SW U.S.
(Nielson & Gill, 1984): CA
(Signoret, 1854): Eastern U.S. into western Canada and CO.
Many members of this genus are brightly coloured and distinctive, white others can be drab and highly variable. The wings are often striped and the heads of many species are boldly marked with various patterns, but some are bare such as in G. coccinea and G. fennahi.
a very wide range of habitats from temperate rainforests to deserts.
Polyphagous—a wide range of vascular plants
This genus is a taxonomic mess. No major revision has been made to the genus since Young 1977 and many decisions were made in that revision that still cause confusion today. This genus is likely polyphyletic, holding a number of potential genera. Over time, some select species have been split off from the main genus into genera such as Allogonia and Amphigonalia, but some species which should belong in these genera are still under Graphocephala. Revising this large group would be an extensive task and is likely very far off (especially since, even though these species may belong to multiple genera, they are all closely related), so the taxonomy on BugGuide follows some opinions of experts to better organise the genus.
We have split the genus up into three major "species groups" on the site, but these are provisional/informal and are not true taxonomic ranks, hence the quotes. These help break the genus up into more manageable sections. "Group" Graphocephala covers the members of the genus which are referred to as "Candy-striped" Graphocephala. The status of these species within the genus is currently very stable (relative to the other 'groups') and they are readily identifiable to group section—this group is also based on published work relating to genital structure.
"Group" Hordnia is less clear-cut and is based on unpublished opinions of Andy Hamilton—it's much more provisional in nature. The only species that was truly a member of the defunct genus Hordnia is G. atropunctata—the other species listed in the 'group' are morphologically similar. Hamilton had the opinion that these species all be treated under the genus Hordnia and, for a time, BugGuide followed this concept. However, these species all currently reside under Graphocephala.
Most complicated is the 'group' Neokolla/Keonolla, based on a very confusing taxonomic history. Authors have treated members of this group over a range of genera and their taxonomic status is highly unstable. Under the current taxonomy, the genera Neokolla and Keonolla have been synonymised with Graphocephala. These species are often more drab in colouration with very bold and intricate markings on the head—some are extremely similar morphologically (though they may not all belong to the same genus). Currently, one genus has been divided from this group—Amphigonalia—which is often denoted by an 'M-shaped' mark on the head. To further complicate things, not all taxonomists agree on the status of the species in this group—we have done our best to find a reasonable system based on the opinions of a wide range of hopper experts. The taxonomy under this page will likely be under regular subject to change.
Keep in mind that these groups are not at all clear-cut. Graphocephala ignava morphologically overlaps with all of these groups. The nymphs of the 'groups' Graphocephala and Hordnia can be identical. Amphigonalia nymphs are identical to those of 'group' Neokolla/Keonolla (where the Amphigonalia species are currently listed here). Until a revision is published and molecular work is done, this genus will remain a bit of a nightmare.
Graphogonalia evagorata — a neotropical species recently found in Texas which bears strong resemblance to Graphocephala
Hortensia similis — a species widespread in the neotropics, sometimes confused for 'group' Hordnia (though the ranges do not overlap)
Sibovia — a heavily-striped genus that can be confused with Graphocephala