PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 112(1):120-132. 1999. The Hawaiian parthenopid crabs of the genera Garthambrus Ng, 1996, and Dairoides Stebbing, 1920 (Crustacea: Decapoda: Brachyura) Peter K. L. Ng and S. H. Tan Department of Biological Sciences, National University of Singapore, Lower Kent Ridge Road, Singapore 119260, Republic of Singapore Abstract. — The taxonomy of four species of deep-water parthenopid crabs, Garthambrus stellata (Rathbun, 1906), G. lacunosa (Rathbun, 1906), G. com-planata (Rathbun, 1906) and Dairoides kusei (Sakai, 1938) from Hawaii is treated. Dairoides kusei is recorded from Hawaii for the first time. The iden-tities of G. stellata, G. lacunosa and G. complanata are clarified, with detailed comparisons and figures provided. Despite earlier reports, there are no inter-mediates between these three species. A key to the genus Garthambrus is provided. Rathbun (1906), in her treatment of the Hawaiian Brachyura, had originally recog-nized eight parthenopid species from these islands. One species, Harrovia truncata Rathbun, 1906, was transferred to a sepa-rate genus (Cyrtocarcinus Ng & Chia, 1994) in the Xanthidae by Ng & Chia (1994). Another species, Parthenope (Pla-tylambrus) stellata Rathbun, 1906, was originally established with three subspecies, P. (P.) stellata stellata, P. (P.) stellata la-cunosa Rathbun, 1906, and P. (P.) stellata complanata Rathbun, 1906. Garth (1993) reappraised the validity of these three taxa and regarded them as distinct species. He briefly commented that the features used by Rathbun (1906) to separate the three vari-eties were good species characters. Al-though Garth examined the type series of all three taxa, he did not comment much about them or figure any of the types. This despite the fact that one taxon, P. (P. ) com-planata, had never been figured before. Nor did he comment on specimens which Rath-bun (1906) had regarded as being interme-diate between the three species. In describ-ing a new species (Parthenope cidaris) from Australia, Garth & Davie (1995) pro-vided photographs of the types of P. (P.) stellata, P. (P.) lacunosa and P. (P.) com-planata but did not make any additional comments other than again stating briefly that all three taxa were good species. Sakai (1938, 1976) had commented that P. (P.) lacunosa (as a subspecies) was a junior synonym of Lambrus (Parthenopo-ides) pteromerus Ortmann, 1893, a species which he transferred to the genus Tutankh-amen Rathbun, 1925. Garth (1993), how-ever, disagreed, commenting that P. (P.) la-cunosa lacked the lamellar ridges lining the afferent channels on the carapace found on Tutankhamen cristatipes (A. Milne Ed-wards, 1880), the type and only species of the genus. On the basis of Garth's (1993) redescription of P. (P.) stellata and his comments on P. (P.) lacunosa and P. (P.) complanata, Ng (1996) subsequently trans-ferred all three species to the genus Gar-thambrus Ng, 1996. Nine species of Parthenopidae are cur-rently known from the Hawaiian islands, Garthambrus stellata (Rathbun, 1906), G. lacunosa (Rathbun, 1906), G. complanata (Rathbun, 1906), Platylambrus nummifera (Rathbun, 1906), Rhinolambrus lamelligera
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