Orthoptera of North Carolina
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View Acrididae Members: NC Records

Melanoplus decorus Scudder, 1897 - Decorated Spur-throat Grasshopper


Adult female
Adult male
Taxonomy
Family: Acrididae Subfamily: Melanoplinae Tribe: Melanoplini
Comments: Melanoplus is our largest genus of Orthopterans, with over 350 species occurring in North America (Cigliano et al., 2017). 38 species have been recorded in North Carolina. Rehn and Hebard (1916a) included decorus in the Decorus species group, which also include M. nubilus and M. attentuatus in North Carolina, and M. australis south of our area.
Species Status: The type specimen was collected by Parker-Maynard at "Dingo Bluff" in North Carolina (Scudder, 1897). This locality name was also used for other species collected by Parker-Maynard and has been repeated in the literature in subsequent descriptions (e.g., Brimley, 1938). The site name, however, appears to be an error for Pungo Bluff (Rehn and Hebard, 1916a), a point of land projecting into Albemarle Sound located on the south side of Hyde County.
Identification
Field Guide Descriptions: Online Photographs: BugGuide, Google Images,  iNaturalist, GBIFTechnical Description, Adults/Nymphs: Scudder (1897); Blatchley (1920)                                                                                  
Comments: A small, short-winged (flightless) grasshopper. Adults are yellowish-green to golden-yellow with black markings on the head behind the eye, a black stripe on the sides of the thorax, and black blotches on the dorsal sides of the abdomen. Legs are unmarked. Coloration and pattern are similar to several other species in the Decorus species group (of Rehn and Hebard, 1916a), but the black stripe on the sides of the thorax usually extends at least slightly and/or narrowly onto the metazona whereas in nubilus and attentuatus it tends to end sharply at the sulcus between the prozona and metazona (but with some exceptions) (Scudder, 1897; Rehn and Hebard, 1916a). Eotettix pusillus, which co-occurs with decorus, is another similar species but has an unbroken white crescent behind its eye, often has a broken rather than continuous black stripe on the sides of the thorax, and has yellowish rather than greenish hind tibiae.
Structural Features: Decorus is most safely distinguished from M. nubilus and attenuatus by the shape of the expanded end of the male cerci: in decorus, this knob is rounded rather than subtruncate, angulated, or somewhat bifid as in nubilus and attenuatus (Rehn and Hebard, 1916a; Blatchley, 1920). The furcula is at least 1/3 as long as the supra-anal plate and there is a strong tubercle located at the upper edge of the subgenital plate in decorus, neither of which is characteristic of the other two species (Rehn and Hebard, 1916a; Blatchley, 1920). Eotettix pusillus is also easily distinguished from decorus by its sub-conical cerci and by the shape of its fore-wings, which are nearly circular rather than oval.
Structural photos
Nymphal Stages and Development: Nymphal stages have not been described
Distribution in North Carolina
County Map: Clicking on a county returns the records for the species in that county.
Adult Dates:
 High Mountains (HM) ≥ 4,000 ft.
 Low Mountains (LM) < 4,000 ft.
 Piedmont (Pd)
 Coastal Plain (CP)

Click on graph to enlarge
Habitats and Life History
Habitats: All of our records come from wet, open, herbaceous swales. Most come from wet longleaf pine savannas, with some also occurring in nearby powerline clearings or along roadside ditches. In mainland Dare County, populations appear to be associated with boggy openings in pocosins; several were seen in an artificially cleared area that contained populations of pitcher plants, sundews, cottongrass, and cranberries, all characteristic of nearby tracts of low pocosin. No individuals have been found in dry habitats, including longleaf pine-dominated sandhills.
Diet: Captive adults feed on the leaves of forbs, including the traps of Venus Flytraps (Hall and Sullivan, 2003)
Observation Methods: Adults are active during the day and are easy to spot in low savanna vegetation
Abundance/Frequency: Usually fairly common and occasionally abundant in savanna habitats
Adult Phenology: Adults have been recorded from early June to early October
See also Habitat Account for Wet, Sandy, Fire-maintained Herblands
Status in North Carolina
Natural Heritage Program Status: SR
Natural Heritage Program Ranks: G2G3 S2S3
State Protection: Listed as Significantly Rare in North Carolina by the Natural Heritage Program. It has no legal protection, however, although permits are required to collect it on state parks and other public lands.
Comments: This species is highly associated with wet savannas and other boggy wetlands, all of which have greatly declined since Colonial settlement due to conversion to agriculture and silviculture. Since the 1950s, when suppression of wildfires became effective, still more habitat losses have occurred in all but habitats where fire is still frequent, mainly in preserves managed through use of prescribed burns. Unlike moth species associated with the same habitats, Melanoplus decorus may survive a fire as underground eggs; it is often abundant in savannas following a burn, at least where the burn occurred early in the year. The inability to fly, however, limits its ability to disperse and once gone from a particular site, it may not be able to recolonize if there are no areas of suitable habitat directly connecting it to other occupied areas. It can, however, make use of at least some forms of disturbed habitats, at least where they have the same moisture and herbaceous features of natural savannas. Populations inhabiting low pocosins may be fairly stable, as these habitats are maintained by hydrological factors rather than frequent fire. Those sites, however, are threatened by sea-level rise; the vast pocosins of the Dare County mainland are believed to be especially at risk due to salt-water intrusion, which rapidly destroys peatlands.

Image Gallery for Melanoplus decorus - Decorated Spur-throat Grasshopper

Recorded by: Mark Basinger
Sampson Co.
Comment: 		Recorded by: Mark Basinger
Sampson Co.
Comment:
Recorded by: Larry Chen
Carteret Co.
Comment: 		Recorded by: Ed Corey
Onslow Co.
Comment:
Recorded by: Ed Corey
Onslow Co.
Comment: 		Recorded by: Stephen Hall and Ed Corey
Bladen Co.
Comment: Identity based on association with a collected and confirmed male
Recorded by: Jamie Cromartie and Steve Hall
Bladen Co.
Comment: 		Recorded by: Steve Hall
Craven Co.
Comment: Adult male