Notes on Indo-West Pacific species of Macrophthalmus (Crustacea, Brachyura)

The author examined material of Sesarma and Macrophthalmus in the collection of the Leiden Museum during a visit made in 1970. His main purpose was to check specimens identified by previous authors and take photographs of some of them. For the Macrophthalmus species, the work of Barnes (1971) has in the mean time cleared up some of the problems which he was considering, this is especially true for M. brevis and M. quadratus. The status of some other species remains unsatisfactory, however, and the second part of the present note is devoted to one of those: Macrophthalmus telescopicus of authors. The same visit provided the author with an opportunity to examine a collection of unidentified material from New Guinea. A new species of Macrophthalmus sorted out during that examination was later sent to him on loan for study. It is described as Macrophthalmus holthuisi nov. sp. in the first part of the present paper. I. A NEW SPECIES OF MACROPHTHALMUS FROM NEW GUINEA Macrophthalmus (Mareotis) holthuisi nov. spec. (text-fig. 1a, b, pl. 1 fig. Α-C, pl. 2 fig. A, B) Material. — Mangroves near Mandon, a small village between Mokmer and Bosnek, south east coast of Biak Island, Western New Guinea; in mud; 20 March 1955; leg. J. Sisselaar and L. B. Holthuis, no. 723. — 1 ♂ holotype, 6X9 mm (RMNH. Crust. no. D 27452), 1 ♂ paratype, 4.0 Χ 5.8 mm (RMNH. Crust. no. D. 27453). Description. — Holotype ♂. The front is broad and deflexed, the frontal width measures 0.29 times the carapace width. The anterior margin of the front is bilobed, the lateral margin is gently oblique towards the supraorbital border and has no marked constriction between the eye peduncles.