217 RAFFLES BULLETIN OF ZOOLOGY 2019 The vampire crabs of Java, with descriptions of five new species from Mount Halimun Salak National Park, West Java, Indonesia (Crustacea: Brachyura: Sesarmidae: Geosesarma) Peter K. L. Ng 1 & Daisy Wowor 2 Abstract. Six species of vampire crabs, Geosesarma noduliferum (De Man, 1892), G. confertum (Ortmann, 1894), G. rouxi (Serène, 1968a), G. bicolor Ng & Davie, 1995, G. dennerle Ng, Schubart & Lukhaup, 2015, and G. hagen Ng, Schubart & Lukhaup, 2015, are known thus far from Java, Indonesia. All are endemic to the island. Surveys in and around Mount Halimun Salak National Park in West Java showed that the sesarmid crab fauna for the island is much richer, and five new species are described. The new taxa are described, figured, and compared with their closest congeners. Two poorly known species, G. confertum and G. rouxi are also re-diagnosed and figured. A key to the known species of Geosesarma from Java is also provided. Key words. semiterrestrial crab, Indonesia, Java, taxonomy, new species, protected areas RAFFLES BULLETIN OF ZOOLOGY 67: 217–246 Date of publication: 3 April 2019 DOI: 10.26107/RBZ-2019-0018 http://zoobank.org/urn:lsid:zoobank.org:pub:0656D7C5-0498-40B6-9348-284800EE671D © National University of Singapore ISSN 2345-7600 (electronic) | ISSN 0217-2445 (print) 1 Lee Kong Chian Natural History Museum, Faculty of Science, National University of Singapore, 2 Conservatory Drive, Singapore 117377, Republic of Singapore; Email: peterng@nus.edu.sg 2 Division of Zoology, Research Center for Biology, Indonesian Institute of Sciences (LIPI), Jalan Raya Jakarta Bogor Km 46, Cibinong 16911, Indonesia; Email: daisy_wowor@yahoo.com * Both authors contributed equally to this work INTRODUCTION The freshwater sesarmid crab fauna of Java has been increasing studied in recent years, and six species of Geosesarma De Man, 1892, and two species of Karstarma Davie & Ng, 2007, are now known (cf. Ng et al., 2015; Wowor & Ng, 2018). The diversity of Geosesarma in particular, popularly known as vampire crabs, is especially high, and some 59 species are now known from the Andamans, Thailand, Malaysia, Indonesia, Papua New Guinea, Philippines, and Taiwan (Ng, 2017). As most of these species practice direct development (i.e., their large eggs hatch into very advanced non-feeding zoeae or as juvenile crabs (cf. Ng, 1988; Ng & Tan, 1995; Soh, 1969), many Geosesarma species have very restricted distributions, with different species sometimes occurring just 10 km from each site (see Ng et al., 2015), compounding the challenge for taxonomists. From West Java, three species are known at present: G. noduliferum (De Man, 1892) [Bogor], G. confertum (Ortmann, 1894) [Tjibodas or Gunung Gede], and G. bicolor Ng & Davie, 1995 [Ujung Kulon,], with two species from Central Java: G. dennerle Ng, Schubart & Lukhaup, 2015 [Cilacap], and G. hagen Ng, Schubart & Lukhaup, 2015 [Cilacap]; and one species from East Java: G. rouxi (Serène, 1968a) [Poedjon]. Collections in and around Mount Halimun Salak National Park (or Taman Nasional Gunung Halimun Salak) in West Java and Banten Provinces in 2015 and 2016 as part of the Indonesia-German INDOBIOSYS (Indonesian Biodiversity and Information System) project resulted in a good collection of Geosesarma specimens. Additional collections were subsequently made in 2017. A joint study of this material and other specimens obtained from several previous surveys around Bogor and Cipanas of Banten Province by the second author showed that five species are represented, all of which are new to science. These new species, as well as the current taxa, are diagnosed, figured and compared with their closest species. A new genus and new species of gecarcinucid crab has already been described from near the summit of Mount Halimun (Ng & Wowor, 2018). MATERIAL AND METHODS Material examined is deposited in the Museum Zoologicum Bogoriense (MZB), Cibinong, Bogor, Indonesia; and the Zoological Reference Collection (ZRC) of the Lee Kong Chian Natural History Museum (ex-Raffles Museum of Biodiversity Research), National University of Singapore. Indonesian words use in the text are S. or Sungai for river or stream; Gunung for mountain; Ds. or Desa for village; Kp. or Kampung for hamlet. The collectors were D. Wowor, U. Nurhaman, and S. Sauri, which is written as D. Wowor et al., unless otherwise stated. Taxonomy & Systematics