North American Delphacidae

Scope

Pissonotus quadripustulatus, Malaxa occidentalis, Ugyops stigmata

(Left to right) Pissonotus quadripustulatus (Delphacinae, Delphacini); Lamaxa occidentalis (was Malaxa; Delphacinae, Tropidocephalini); Ugyops stigmata (Asiracinae: Ugyopini).

Stobaera tricarinata

Stobaera tricarinata

This site compiles information (especially taxonomic) about delphacid planthoppers (Hemiptera: Fulgoroidea: Delphacidae), with a particular emphasis on American north of Mexico, although I have subsequently expanded the scope to include all families of planthoppers (as well as the remaining New World delphacid genera). The content of this site is continually being developed and updated.  The purpose of this site is to present general and technical information concerning planthoppers, including those species that are, or may be invasive, in North America.  Delphacid planthoppers are of particular interest as potential pests and invasive species both from direct feeding on economic plants and as vectors of plant diseases, especially viruses.

The central focus of this website is the development of online identification tools with state and federal identifiers, port inspectors, USDA APHIS PPQ, and extension services in mind in particular, but also both biological scientists and a more general audience should find them of value. Initially, I had intended to build interactive keys using Lucid3 software, but the software proved too cumbersome and only a draft key was completed.  Instead, so far, I have published a traditional paper key supplemented by this site that I have been updating iteratively.  The site has recently been moved to a new server, and I have updated much of it in the process.  Some pages remain on the old server and I will move them as they are discovered, and some links may not work properly, which I will fix as I discover them.

This site includes a searchable bibliography of post-1940 literature (plus a digital PDF library for select pre-1940 literature), primarily post-1940 (earlier literature is on DrMetcalf).

Delphacid classification synopsis and list of world genera  (includes links to delphacid genus-pages).

A synopsis of New World genera is here.

What are delphacids?

“Planthoppers” is a general term for any insect in the superfamily Fulgoroidea (or infraorder Fulgoromorpha, if all extinct forms are included). Planthoppers are insects related to leafhoppers, treehoppers, spittlebugs and cicadas (but these are in the infraorder Cicadomorpha).  Most species are between 2-4 mm in size (ranging from ~1.5 – ~10.0 mm). Delphacids are easily distinguished from other planthoppers and similar insect families (viz. the cicadomorphs) by the presence of a large, movable spur (the ‘calcar’) on the apex of the hind tibiae.  Delphacids are mostly grass-feeders (often in wet – or at least mesic – situations), although some feed on sedges, rushes, and broad-leaved plants, especially those in the aster family. Endemic delphacids in Hawaii have evolved onto many dicot taxa.

The calcar of Syndelphax alexanderi.
The calcar of Syndelphax alexanderi.

Number of species

Worldwide, there over 2,100 described species of delphacids (my count: 2,163 species in 378 genera, FLOW currently [14 Nov 2017] lists 416 genera and 2,209 species);  however, there are also many species that are not described (i.e., not “known to science”).  Most new species are from the tropics, but some new species will turn up from otherwise well-known regions, such as the eastern United States.  North of Mexico, there are 61 genera and 312 species in the U.S. (in 4 subfamilies and 4 tribes) plus an additional 5 genera and 26 species in Canada (total 66 genera, 338 species).  Canada has 39 genera and 146 species by my count.  From Mexico and south (including Caribbean) there are 67 genera and 304 described species (excluding 1 nomen dubium and 2 subspecies).  In total for the New World, there are 100 genera and 576 species.

Distribution

Delphacids are broadly and rather evenly distributed from tropical to arctic latitudes, including all continents and islands, except Antarctica.  While species diversity may eventually be shown to be highest in moist tropical regions, at present most species have been described from north temperate regions.  Far northern regions, such as Alaska, northern Canada, and Siberia have surprisingly diverse faunas (however, the reported fauna of Iceland is a single species).  Distant oceanic islands such as Hawaii and the Galapagos have endemic faunas and adventive species (Hawaii has 143 endemic species plus 10 adventive).

Worldwide distribution of Delphacidae from FLOW (14 Nov 2017)
Worldwide distribution of Delphacidae from FLOW (14 Nov 2017) (gaps – e.g., in Africa – are lack of data)

Suggested citation of web site:

 

Bartlett, C. R. and contributors. 2017 (and updates). Delphacid planthoppers of North America. Available at http://canr.udel.edu/planthoppers/north-america/north-american-delphacidae/, accessed on [date].

Alternately

Bartlett, C. R. and contributors. 2017 (and updates). Planthoppers of North America. Available at http://canr.udel.edu/planthoppers/, accessed on [date].

Contact: Bartlett[at]udel.edu.

Stiromoides maculiceps (Horvath, 1903)
Stiromoides maculiceps (Horvath, 1903)

Eurysa_maculiceps-labelcrop

 

Photographs, unless otherwise indicated, are by Kimberley Shropshire, Charles Bartlett, or UD Dept. Entomology grad students.  Such photos were supported by USDA NRI Grant No. 2009-55605-05006, and are available (with attribution) for educational, scientific, or other non-commercial use based on a creative commons license.  Photos from other sources are used by permission and attributed to that source – permission for further use is not mine to grant and should be sought from the attributed source.