Question: What animal with only four extant species was the name borne by four ships of the Royal Navy
Sentence (from "Mangrove horseshoe crab"): The biology, ecology and breeding patterns of "C. rotundicauda" and the two other Asian horseshoe crab species, "Tachypleus gigas" and "Tachypleus tridentatus", have not been as well documented as those of the North American species "Limulus polyphemus".
Relevant evidence: No