Morphological ontogeny of Sphaerozetes olympicus sp. nov. (Acari: Oribatida: Ceratozetidae) from Greece, with comments on Sphaerozetes

Abstract

Abstract In this study we describe and illustrate the morphological ontogeny of a new ceratozetid oribatid mite, Sphaerozetes olympicus sp. nov. from moss on the rocky soil in a pine forest on the slope of Olympus Mtn. (Greece). The adult of S. olympicus is similar to that of Sphaerozetes orbicularis (C.L. Koch, 1835), but has a rostrum with two shallow incisions, a short lamellar cusp, most notogastral setae vestigial (alveolar) and seta p1 longer than others of the p-series; in S. orbicularis the rostrum has two deep incisions, the lamellar cusp is of medium size, most notogastral setae are distinguishable (though minute) and p1 is as short as other setae of the p-series. The juveniles of both species have most gastronotal setae short, but S. olympicus has seta h1 distinctly longer and thicker than other gastronotal setae, whereas in S. orbicularis this seta is short. Moreover, in S. olympicus the prodorsal seta le is thicker than in and blunt, whereas in S. orbicularis le is as thin as in and acuminate...