Previous records. described for the South Shetland Islands and Weddell Sea (15–424 m), rediscoverd in the Ross Sea (Rehm et al., 2007, 410 m); Prydz Bay several stations (unpublished data).
Diagnosis. Carapace without teeth on dorsomedian line or laterally on carapace; uropod endopod with distal article half as long as proximal.
New records. (Figure 16) SE Weddell: ANT XV #89-E: 4 specimens; ANT XV #130: 2 specimens; ANT XV #134 AGT: 1 specimen; ANT XV #142: 1 specimen; ANT XV #272: 2 specimens, ZMH: K 42939.
Remarks. The new material from the SE Weddell See is most similar to this species; however, there are a few adult specimens with a small dorsomedian tooth at the anterior margin of the rudimentary ocular lobe. The lateral parts of the carapace have no teeth, the teeth along the anterior margin of the carapace are small and unpronounced.
There are minor differences in the dissected extremities: A1, accessory flagellum is shorter than the basal article of the main flagellum in the ANT XV-form, but equal in length in L. parasiphonatus and weddelli (see below); Mxp3, ischium has one tooth in the ANT XV-form like in L. weddelli but unlike in L. parasiphonatus; the teeth of the dorsomedian line of the carapace are zero in L. parasiphonatus, one in the ANT XV-form, and two in L. weddelli; the length proportion of the uropod endopod basal to distal article in the ANT X-form is rather like in L. weddelli (2.6) than in L. parasiphonatus (2.4).