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Species Trimerotropis helferi - Helfer's Dune Grasshopper
Classification Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Orthoptera (Grasshoppers, Crickets, Katydids)
Suborder Caelifera (Grasshoppers)
Family Acrididae (Short-horned Grasshoppers)
Subfamily Oedipodinae (Band-winged Grasshoppers)
Tribe Trimerotropini
Genus Trimerotropis
Species helferi (Helfer's Dune Grasshopper)
Other Common Names Speckled Sand Grasshopper
Synonyms and other taxonomic changes Trimerotropis helferi Strohecker, 1960. Type locality: Cleone, Mendocino County, California
Microtes helferi (Strohecker) Otte 1984
Explanation of Names This species strongly resembles members of Microtes in morphology, habitat choice, and behavior, and was moved to that genus by Otte. However, the similarities in appearance may be convergent adaptations to a sand habitat, and not due to close kinship. Based on chromosome configuration [with metacentric chromosomes], this species appears to belong within "Section B" of Trimerotropis as that genus is currently circumscribed. However, it is also possible that the chromosome similarities are coincidental (unlikely, but definitely possible), and that this really is a species of Microtes. A proper resolution of this question will require more study.
Size about 20 to 35 mm (females distinctly larger and stockier than males).
Identification Rather wide-bodied and short-winged for a Trimerotropis, distinctly hairy (mostly sides and below). Coloring usually light grayish, covered with dark speckling and small spots, and with dark diagonal cross bands on hind femora. As seen with wings folded, there is commonly a pale mid-longitudinal stripe. Hind tibiae yellowish to brownish; hind wings clear, nearly colorless, but in good lighting a faint yellowish to greenish tinge may be seen, with narrow cloudy curved dark cross band.
Similar in appearance to Microtes species, which occur further south along the coast in similar habitats. Microtes are even broader in proportions, with top of pronotum wider, flatter, and more sharply margined laterally; with wings often proportionately shorter; with dark portion of hind wing nearer to apex.
Range Pacific Coast; recorded from Grays Harbor County in Washington to Mendocino County in California.
Habitat Found on sand in coastal dune areas. Seems to be associated with dune inhabiting Artemisia species.
Life Cycle Overwinters as eggs, hatching in spring or summer, with adults late June to mid October
Remarks Very well camouflaged in sand, and often very difficult to see. Often not noticed due to small size and inconspicuous coloration, even when flying.
Males are alert, and even though flights are usually relatively short, they are quick difficult to approach. Females are equally alert, but often stay still rather than flying. They are somewhat clumsy fliers, and often choose to simply hop, rather than to take to the air, even when they do move away. They may be seen trying to bury themselves by kicking sand away with their legs. They can bury themselves rather quickly, apparently not just to sleep or avoid heat or cold, but also to hide.
Print References
Otte, Daniel, 1981. 'The North American Grasshoppers', volume II, Acrididae, Oedipodinae (1)
Weissman, David B. & D.C.F. Rentz, 1980. 'Cytological Morphological, and Crepitational Characteristics of the Trimerotropine (Aerochoreutes, Circotettix, and Trimerotropis) Grasshoppers (Orthoptera: Oedipodinae)', Transactions of the American Entomological Society 106: 253-272
Weissman, David B., 1984. 'Notes on the Autecology, Cytology, Morphology, and Crepitation of Trimerotropis Grasshoppers (Orthoptera: Oedipodinae)', Pan-Pacific Entomologist 60(4): 269-278
Contributed by David J. Ferguson on 28 May, 2010 - 10:44am Last updated 30 August, 2017 - 7:39pm |
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