Tiger beetles in southeast Missouri
February 17, 2012 6 Comments
The first three papers clearly painted a rather gloomy picture—H. circumpicta johnsonii is possibly extirpated from saline spring habitats in central Missouri, D. pruinina is limited to a 2.5 mile stretch of roadside habitat in western Missouri, and C. celeripes is restricted to a few patches of critically imperiled loess hill prairie habitat in extreme northwestern Missouri. Happily, prospects for T. carolina and C. cursitans in Missouri are much better. While both are limited in the state to the southeastern lowlands, our surveys indicated that populations are sufficiently robust and widespread in the area to alleviate any concerns about the potential for extirpation. Tetracha carolina in particular was found abundantly in agricultural habitats and appears to have adapted well to the extensive modifications caused by conversion of the cypress-tupelo swamps that formerly covered the region. Cylindera cursitans (Fig. 2) hasn’t shown nearly the same adaptive capability as T. carolina; however, it has nevertheless found suitable refuge in the ribbons of wet, bottomland forest that persist between the Mississippi River and the levee systems that protect the region’s farmland. For a time it seemed that the same habitats along the St. Francois River that bound the western side of the region weren’t suitable for the species, but after much searching (in often tough conditions!) Kent finally managed to locate a population on the Missouri side of the river opposite a known population in Arkansas.
Both of these species illustrate how healthy populations of insects are able to hide right beneath our noses. Previous to our surveys, records of T. carolina and C. cursitans in southeastern Missouri were scarce (the latter consisting of a single specimen in the Enns Entomology Museum at the University of Missouri in Columbia, and with considerable searching required before the first field population was finally located). In both cases, perceived rarity was a result not of actual rarity, but rather specific habitat requirement or unusual behavior. While I get great satisfaction out of finding populations of “rare” species and increasing our understanding of their habitat requirements, I also can’t help but wonder if they truly are rare and how many populations I might still have missed—populations that I would have found had I searched in a slightly different manner or at a slightly different time.
Fothergill, K., C. B. Cross, K. V. Tindall, T. C. MacRae and C. R. Brown. 2011. Tetracha carolina L. (Coleoptera: Cicindelidae) associated with polypipe irrigation systems in southeastern Missouri agricultural lands. CICINDELA 43(3):45–58.
MacRae, T. C., C. R. Brown and K. Fothergill. 2011. Distribution, seasonal occurrence and conservation status of Cylindera (s. str.) cursitans (LeConte) (Coleoptera: Cicindelidae) in Missouri. CICINDELA 43(3):59-74
Copyright © Ted C. MacRae 2012