Reference 18274

Some 25 years after the discovery of Remipedia and their recognition as a new class of Crustacea, many biologic aspects of these hermaphroditic arthropods are still poorly understood. For example, practically nothing is known about the modes of reproduction and development in remipedes. To date, the smallest individuals found measured about 3.5 mm, while the mean maximum body length of adult specimens is 27.2 mm, with a recorded maximum of 45.1 mm in Godzillius. Remarkably, the trunks of all small specimens examined thus far were composed of at least 15 somites, and their general morphologic appearance resembled that of adults. Despite numerous attempts, earlier developmental stages or smaller and/or shorter individuals could not be found. During a diving expedition in March 2006, we were able to collect remipede nauplii for the first time. We describe the development of Remipedia based on five metanaupliar stages in the range of 1.6 - 2.2 mm, and a juvenile specimen (3.7 mm) that exhibits distinct transitional developmental features.