New Studies on the Water Mite Genera Neomamersa Lundblad and Kawamuracarus Uchida (Acarina, Limnesiidae) from North America

Abstract

Three new species and subspecies of Neomamersa are described from interstitial waters in North America. These are N. hexapora (New Mexico), N. lundbladi paucipora (Arizona, New Mexico) and N. (Meramecia) ocularis (New York). This latter species possesses well developed, pigmented lateral eyes. A new species of Kawamuracarus, K. serratipalpis, is described from Arizona. The taxonomic importance of the fourth leg claws in the Limnesiidae is discussed. INTRODUCTION Cook (1963) described three species of Neomamersa and one species of Kawamuracarus from interstitial waters in North America. These were N. lundbladi, N. (Meramecia) anisitsipalpis, N. (Meramecia) perplexa, and K. Iongisetus. The present study2 treats an additional three species and subspecies of Neomamersa and one of Kawamuracarus collected during the summers, of 1964 and 1966. In presenting measurements in this paper, those of the holotype and a representative paratype of the opposite sex (when available) are given first. If a series of specimens is available, the range of variation is given in parentheses following the measurements of the primary types. Holotypes and representative paratypes will be placed in the Field Museum of Natural History (_ Chicago Natural History Museum). Genus Neomamersa Lundblad Two of the new species of Neomamersa exhibit characters which alter the previous concept of the genus. One species, N. ocularis, possesses pigmented lateral eyes. This species lacks integumental pigmentation and was taken in a collection containing numerous other interstitial forms. N. ocularis is. a true phreaticolous species. The presence of pigmented eyes in this species suggests that the genus Neomamersa evolved as a surface water group which later invaded subsurface waters. N. hexapora is the first member of the subgenus Neomamersa with a reduced number of acetabula. Six pairs of acetabula are present in this species and they are arranged much as in the subgenus Meramecia. Some of the acetabula pairs in N. hexapora share either a common external or internal pore (Fig. 5) and this suggests evolution from some triacetabulate ancestor. The structure of the genital field in N. hexapora provides insight into origin of the differences between male 'Contribution no. 188 from the Department of Biology, Wayne State