European Conference on Artificial Intelligence · 1992 · 137 citations · 0 references
<i>Rhynchosporamesoatlantica</i><b>sp. nov.</b> (Cyperaceae) is described, illustrated, and compared with morphologically similar species. <i>Rhynchosporamesoatlantica</i> is known only from southern Delaware, southeastern Maryland, and southern New Jersey, all within the Mid-Atlantic region of the U.S.A. It inhabits sunny, wet margins of natural, shallow, nutrient-poor, seasonal ponds of the Coastal Plain. Narrow leaf blades; fruits obpyriform in outline; faces of mature fruits possessing a central, pale, well-demarcated disk; and fruit tubercle margins denticulate for most of their lengths indicate <i>R.mesoatlantica</i> is most similar to <i>R.filifolia</i> and <i>R.harperi</i>. <i>Rhynchosporamesoatlantica</i> is unique in its fruit dimensions, scales intermediate in length between <i>R.filifolia</i> and <i>R.harperi</i>, and relatively long fruit stipe. The NatureServe rank of Critically Imperiled and the IUCN rank of Endangered appear warranted for <i>R.mesoatlantica</i> because only six populations are known to be extant, most quite small and isolated; all populations occur within a small geographic area; populations have declined; and serious threats confront the survival of the species.