Revision of modest grasshopper (Agroecotettix Bruner 1908) with 16 new species from the United States and Mexico
NEWS - JoVonn Hill of Mississippi State University revised and established 16 new species of modest grasshopper (Agroecotettix Bruner 1908), a group of grasshoppers inhabiting open scrub, dry desert plains and scrub from central Texas to southeastern New Mexico, south to central Mexico.
Bruner (1908) established the genus with the description of Agroecotettix modestus based on a female collected from Ciudad Lerdo, Coahuila, Mexico. Hebard (1922) added Agroecotettix aristus aristus and Agroecotettix aristus crypsidomus from Uvalde and Marathon, Texas, USA, respectively, resulting in three taxa.
The new taxa described are Agroecotettix silverheelsi sp. nov., Agroecotettix xiphophorus sp. nov., Agroecotettix glochinos sp. nov., Agroecotettix texmex sp. nov., Agroecotettix cumbres sp. nov., Agroecotettix burtoni sp. nov., Agroecotettix moorei sp. nov., Agroecotettix chiantiensis sp. nov., Agroecotettix dorni sp. nov., Agroecotettix chisosensis sp. nov., Agroecotettix turneri sp. nov., Agroecotettix quitmanensis sp. nov., Agroecotettix vaquero sp. nov., Agroecotettix forcipatus sp. nov., Agroecotettix idic sp. nov., and Agroecotettix kahloae sp. nov.
Most are endemic to the Chihuahuan Desert, Sierra Madre Occidental and the South Texas Plains. This discovery represents a significant advance in knowledge of desert biodiversity and the ecological complexity of this unique region.
The evolution of other brachypteran groups of North American melanoplines was influenced by Pleistocene glacial cycles affecting river flows, mountain ecosystems and island or dune island isolation resulting in population cycles of contraction, isolation, divergence, expansion and secondary contact processes.
The Chihuahuan Desert stands out as a center of Agroecotettix biodiversity with 11 of the 19 species inhabiting the area, 9 of which are endemic. The vast expanse of the desert is home to a wide variety of plant and animal life, including many endemic species that are specially adapted to dry conditions.
During the Pleistocene, especially the Late Wisconsinan 27,000-11,000 years BC, it was dominated by paperback pine and juniper forests, and the Mapimian vegetation assemblage was dominated by conifer/juniper forests. The establishment of the Chihuahuan desert scrub as a dominant element is not recorded until 8,000-9,000 years BC.
The Edwards Plateau environment during the late Pleistocene (c. 20–14,000 years ago) was largely covered by dark reddish clay and open savanna with tall and short grasses. Drying conditions during the Holocene (c. 10,500–2,500 years BCE) resulted in reduced vegetation cover, leading to gradual degradation of the soil mantle and a shift to short grass and shrub communities.
The Edwards Plateau and surrounding areas, in contrast to the Chihuahuan Desert, are the breeding grounds for the most widely distributed Agroecotettix, A. aristus. This distribution suggests that the species and genus may have originated in the south and spread to their present range during more recent dry periods.
Original research
Hill JG (2024). Desert diversification: revision of Agroecotettix Bruner, 1908 (Orthoptera, Acrididae, Melanoplinae) with descriptions of sixteen new species from the United States and Mexico. ZooKeys 1218: 177-230, DOI:10.3897/zookeys.1218.133703
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