Acridium emarginatum Uhler, manuscript
Acridium emarginatum, nomen nudum Dodge, 1872: 15
Acridium emarginatum Scudder, 1872: 250
Schistocerca lineata Scudder, 1899: 465
Schistocerca scudderi Bruner, 1906: 676, unnecessary replacement name
Schistocerca lineata Scudder (Hubbell, 1960: 71)
Schistocerca emarginata (Scudder) (Vickery and Kevan, 1964: 1555; 1983: 725)
Schistocerca alutacea lineata (Scudder) (Dirsh, 1974: 204)
Cingulum, surfaces or rami not infolded and sinuate, thus making "basal eminence" appear hour-glass shaped, and broad in the middle
Schistocerca lineata is abundant in sandy areas, but also frequently found in other habitats.  Detailed account of its habitat association is found in Hubbell (1960: 43-48).  Criddle (1932) reported that the development takes 39 days from the time of hatching.  He also noted that this species has five nymphal instars.  Sword and Dopman (1999) suggested that the nymphal instars in Texas populations behave as monophagous while the adult instars are polyphagous.  Dopman et al. (2002) found that the populations associated with either Ptelea or Rubus form a monophyletic clade using 16S rRNA and 12S rRNA regions of the mitochondrial DNA.  Although their study demonstrated the lack of gene flow between two host-associated populations, I am hesitant to create a new taxonomic concept at this moment because not much is known about the populations in the midwestern and eastern U.S.  Highly conspicuous individuals from the southwestern states are more robust in form and slightly larger than non-conspicuous ones.  In terms of coloration, specimens from Great Lake regions are brown and highly resemble S. rubiginosa.  Aposematic specimens are never found in northern states although the polymorphism of dorsal longitudinal stripe exists.  In western states, specimens become almost indistinguishable from S. shoshone except on the basis of markings on abdominal tergites.  These specimens have olive green hue, which is rarely observed in either southwestern or eastern populations.  In all cases, however, crucial morphological characters, such as phallic complex and inflated male femurs, are identical.  The reason S. lineata is so polymorphic is unknown, but the fact that it is most widespread seems to suggest that the species is adaptively highly plastic.
Typical form (found in eastern U.S.)
Aposematic form (found in southwestern U.S. including TX and OK)
Brown form (found in Great Lake regions)
Olive green form (found in western U.S. including UT and CO)
LECTOTYPE ♂ [ANSP] Schistocerca lineata Scudder, 1899