| Summary: | FIGURE 1. Distribution of the Elminiinae and early Tetraclitoidea. The earliest record of the Elminiinae is the four plated Protelminius pomahakensis from the Rupelian (early Oligocene) of New Zealand. Assuming a six-plated ancestor to this taxon, parsimony requires a Hexaminius-type first occurring in eastern Australia during the Eocene, from which the four-plated form evolved and dispersed across a proto-Tasman Sea to New Zealand. If Hexaminius had occurred in New Zealand, it would not be unreasonable to expect it in the present warmer northern waters. It was most likely during the Oligocene to early Miocene that Elminius dispersed to South America (shaded arrow); with colonization of the Falkland Islands and the eastern seaboard of South America being facilitated by the opening of the Drake Passage, which had occurred by that time (Scher and Morris, 2006). The dotted line shows the very recent distribution path for Austrominius modestus from Australasia to Europe; although there is a report of single specimen of A. modestus from South African waters – a 1949 record in Sandison (1950), there have been no further records from Africa since then, and we can only assume that it has failed to colonise in the area. Uncertainty about the high Austrominius diversity in a restricted region in South Australia necessitates that these taxa be grouped. A further arrow (dotted and shaded), extending from the Antarctic to what would have been the proto-Tasman Sea, delineates a possible westward dispersal route for the tetraclitoid genus Austrobalanus; which has the earliest records from the Bartonian (middle Eocene) of the Antarctic Peninsula (Buckeridge, 2000). Oceanic patterns at and immediately prior to that time (see Nelson and Cooke, 2001) provided an opportunity for Austrobalanus to have dispersed to southern New Zealand (where it is first recorded from the Rupelian (Oligocene). Extinct genera marked †. Published as part of Buckeridge, John S. & Newman, William A., 2010, A review of the subfamily Eliminiinae ...
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