Krøyer, 1845
Body often dorsally carinate or toothed (Eusirus perdentatus 1; Eusirus properdentatus 1). Rostrum small to large. Eyes reniform or absent. ANT subequal, or ANT I longer than II. Coxae short or medium-large. CX I not produced anteriorly, broadened ventrally. CX IV more or less excavated, with posterior lobe. Mandibular molar strong, columnar, triturative. Inner lobe of MX I with 1-2 apical setae. Inner lobes of MX II broader but not longer than outer, often with strong medial setae. Dactyl of MXP palp not spinose along inferior (inner) margin. P I and II alike (Eusirus properdentatus 2), subchelate, of classic eusirid form. P III-VII elongate, simple. Posterior margin of epimeral plate III serrate or smooth. Exopodites of UR I-II shorter than endopodites. UR III not extended beyond UR I. Telson variable (Eusirus perdentatus 2; Eusirus properdentatus 4): elongate or short, cleft, incised or emarginate.
Twenty two species, mainly benthic, but a few deep-water planktonics.
Eusirus antarcticus Thomson, 1880
Eusirus microps (Inhabits Antarctic waters)
Eusirus perdentatus Chevreux, 1912
Eusirus properdentatus Andres, 1979
In cold Antarctic waters, some benthic species also rise into the pelagic realm. A few of them were found in the Atlantic sector of the Antarctic, at or near the southern border of the region (60-62°S), one species reaching subantarctic waters.