The Euryhaline Copepod Genus Eurytemora in Fresh and Brackish Waters of the Cape Thompson Region, Chukchi Sea, Alaska

Out of Alaska: morphological diversity within the genus Eurytemora from its ancestral Alaskan range (Crustacea, Copepoda)

“…Thus, the angle (A11) was not useful in separating the two groups. E. raboti and E. affinis are distinguished from the remaining specimens by the relatively wide projection of P5X1 40 12 E. composita (Wilson & Tash, 1966) 0.247 (0.001 No single character separates these 12 E. composita specimens from the remaining 28 E. americana specimens. A combination is required of A5: long distal lateral seta on P5X1, the P5X1 projection often lacks hair-like microspinules 28…”

“…1) during June of 2005, primarily in the Northwest Arctic region near Kotzebue (66°53 0 N, 162°36 0 W). These sampling locations were chosen based on previous studies that found high diversity of Eurytemora species within this region (Wilson & Yeatman, 1959;Wilson & Tash, 1966;Heron, 1964). Eurytemora individuals were found in a wide range of salinities (0-28.8 PSU) and habitat types (Appendix Table 3 in Supplementary material).…”

“…Its latitudinal distribution spans from subtropical to subarctic, but with increasing species diversity toward northern latitudes. The region of Alaska and Northeastern Asia constitutes the epicenter of biodiversity for Eurytemora (Wilson & Yeatman, 1959;Johnson, 1961;Heron, 1964;Wilson & Tash, 1966;Heron & Damkaer, 1976), implicating this region as the evolutionary origin for this genus. Of the approximately 21 described species, most have been found in Alaska, and many are endemic to this region (Heron & Damkaer, 1976).…”

“…Several species were described in the late nineteenth century (citations in Wilson & Yeatman, 1959), while a second wave of descriptions followed in the middle of the twentieth century (e.g., Heron, 1964;Wilson & Tash, 1966). Previous species designations within Eurytemora have been largely based on morphological descriptions of specimens from one or a few locations, such that there has been scant understanding of morphological variation within populations, or variation due to seasonal effects or geographic gradients.…”

The Freshwater co-occurrence of Eurytemora Affinis (Copepoda: Calanoida) and Manayunkia Speciosa (Annelida: Polychaeta): Possible relicts of a marine incursion

“…Investigations by Wilson and Tash (1966) and by Tash and Armitage (1967) failed to record Eurytemora affinis in coastal, brackish or freshwater habitats of Alaska although eight other Eurytemora species were recorded . In reviewing the known freshwater records for E. affinis in North America, Katona (1971) stated that E. affinis was primarily a southern species having a northern range limit in the Gulf of St .…”