Systematics and Biogeography of the Desert Crane Flies of Western North America

费城自然科学院的乔恩·盖尔豪斯博士正在研究栖息在北美西南部沙漠地区的鹤类苍蝇的生物多样性和分类关系。尽管鹤蝇通常在潮湿的生境中最多样化和最丰富，但有几个亚群表现出反复、独立的进化和向干旱生境的多样化，这一现象显然是美国西南部在这个原本是全球范围内的昆虫群体中所独有的。主要目标有三个：(1)确定北半球Tipula属新月形蝇亚属的物种亚群，几乎所有的沙漠鹤类种群都起源于该亚属；(2)详细研究了新月形目的3个荒漠鹤类群，对所有新种和已知种进行了描述和图解，确定了各种的地理分布，推测了各群的系统发育历史；以及(3)利用这三个鹤类群的地理范围和进化史知识，以及以前发表的关于北美沙漠昆虫的知识，来综合关于北美沙漠昆虫区系发展和多样化的一般假设。这些研究将利用博物馆中已经存在的标本，以及那些在墨西哥西南部和北部三次收集过程中获得的标本。

Dr. Jon Gelhaus of the Academy of Natural Sciences in Philadelphia is studying the biological diversity and taxonomic relationships of crane flies inhabiting desert regions of the North American Southwest. Although crane flies are typically most diverse and abundant in moist habitats, several subgroups show repeated, independent evolution and diversification into arid habitats, a phenomenon apparently unique to the American Southwest in this otherwise worldwide group of insects. Three main objectives are being pursued: (1) Define the species subgroups within the crane fly subgenus Lunatipula of genus Tipula in the northern hemisphere, from which nearly all of the desert crane fly species groups have arisen; (2) Examine in detail three desert crane fly groups of Lunatipula, describing and illustrating all new and previously known species, determining the geographical distribution of each species and inferring each group's phylogenetic history; and (3) Use knowledge of the geographic ranges and evolutionary history of these three crane fly groups, as well as those previously published for other North American desert insects, to synthesize a general hypothesis regarding development and diversification of the North American desert insect fauna. The studies will utilize specimens already in museums as well as those secured on three collecting trips to the Southwest and northern Mexico.