Paleoglaciologys Grand Unsolved Problem

The paleoglaciological concept that during the Pleistocene glacial hemi-cycles a super-large, structurally complex ice sheet developed in the Arctic and behaved as a single dynamic system, as the Antarctic ice sheet does today, has not yet been subjected to concerted studies designed to test the predictions of this concept. Yet, it may hold the keys to solutions of major problems of paleoglaciology, to understanding climate and sea-level changes. The Russian Arctic is the least-known region exposed to paleoglaciation by a hypothetical Arctic ice sheet but now it is more open to testing the concept. Implementation of these tests is a challenging task, as the region is extensive and the available data are controversial. Well-planned and coordinated field projects are needed today, as well as broad discussion of the known evidence, existing interpretations and new field results. Here we present the known evidence for paleoglaciation of the Russian Arctic continental shelf and reconstruct possible marine ice sheets that could have produced that evidence.

Revision of the Cumacean Family Leuconidae

The family Leuconidae currently contains 99 species. With the exception of Epileucon, all genera in the family were established by 1907. All new species have been subsequently assigned to those genera, gradually producing genera distinguishable on the basis of single characters. In this paper Epileucon is reduced to a subgenus of Leucon as proposed by Bacescu (1988), and the species of Leucon are further apportioned among the subgenera Leucon Kroyer, Macrauloleucon, new subgenus, Crymoleucon, new subgenus, and Alytoleucon, new subgenus. In addition, the new genera Ommatoleucon, Austroleucon, Nippoleucon, and Bytholeucon are proposed, and the genus Coricuma Watling and Breedy is added to this family. The new genus Americuma, with unclear family affiliations, is proposed for a species previously assigned to Heteroleucon. Complete diagnoses are provided for all genera and keys are given to all genera and species.