The first terrestrial isopod (Crustacea: Isopoda: Oniscidea) from Cretaceous Burmese amber of Myanmar Pierre Broly a, * ,S  ebastien Maillet b , Andrew J. Ross c, * a Unit ed’Ecologie Sociale, Universit e Libre de Bruxelles, Campus de la Plaine, Bruxelles, Belgium b Universit e Lille1 des Sciences et Technologies, UMR 8217 CNRS G eosyst emes, B^ at. SN5, Avenue Paul Langevin, 59 655, Villeneuve-d’Ascq, France c Department of Natural Sciences, National Museum of Scotland, Chambers St. Edinburgh EH1 1JF, UK article info Article history: Received 23 December 2014 Accepted in revised form 28 February 2015 Available online 24 March 2015 Keywords: Myanmar Burmese amber Synocheta Woodlice Fossil New species Palaeobiogeography abstract This paper represents the first formal description of a Cretaceous terrestrial isopod (Oniscidea). This unique specimen, a well preserved female in Burmese amber from Myanmar, is described as Myan- mariscus deboiseae gen. nov. sp. nov. It belongs to the clade Synocheta Legrand, 1946 based on the poorly differentiated flagellum of antenna, its small body size and underdeveloped eyes. Its familial position remains uncertain because this group is primarily classified using male reproductive struc- tures. However, comparison with the biogeographical distribution of Recent species of Oniscidea suggests it most probably belongs to the Styloniscidae Vandel, 1952. This specimen and other records of Oniscidea in Cretaceous amber from East Europe indicate that this remarkable group of crustaceans was already highly diversified by the Cretaceous, thus supporting an earlier origin for the group. Finally, this strictly terrestrial Mesozoic isopod represents the earliest formal record of land coloni- zation within Crustacea. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction Within Crustacea, the Oniscidea (Isopoda) are remarkable or- ganisms due to their ability to live on land (Hornung, 2011). Currently, terrestrial isopods, commonly named woodlice, are one of the major groups of soil macrofauna (e.g. Gongalsky et al., 2005; Paoletti & Hassall, 1999; Hornung et al., 2007; Podgaiski et al., 2007) and have an important role in soil process and soil ecosys- tems, particularly as litter decomposers (e.g. Wieser, 1978; Hassall et al., 1987; Kautz & Topp, 2000; Zimmer, 2002; Quadros & Araujo, 2008). Today their distribution is cosmopolitan, extending from the supralittoral level to hot deserts and high altitudes (Vandel, 1960; Warburg, 1993; Linsenmair, 2007). They are partic- ularly common in forest leaf litters, grasslands and sites managed by humans, e.g. gardens. For a long time, terrestrial isopods (Oniscidea) were believed to be a relatively recent group probably because, despite the relatively large size of the suborder (over 3600 species; Schmalfuss, 2003), the fossil record of Oniscidea is quite scarce and, until recently, was restricted to the Cenozoic (Broly et al., 2013). Woodlice are crustaceans, so their exoskeleton is mainly composed of calcium carbonate (CaCO 3 )(Becker et al., 2005; Neues et al., 2007; Hild et al., 2008) with minor amounts of materials resistant to chemi- cal and physical degradation, in particular chitin or sclerotized structures (Girling, 1979; and see Briggs, 1999; Gupta & Briggs, 2011). Therefore, the probability of burial and fossilization in the continental realm is low for these terrestrial crustaceans. However, one particular material can lead to a good preserva- tion of ancient woodlice, and that is amber. Currently, the major part of the oniscidean fossil record comes from Cenozoic amber (Broly et al., 2013). Sometimes, the biomineralized cuticle may be superficially degraded by acidic compounds of fresh resins (Schmalfuss, 1984a), however many ambers, such as Rovno, Baltic, Bitterfeld and Dominican amber have well preserved woodlice through time and several species have been described (Spahr, 1993; Schmalfuss, 1980, 1984a). The regular capture of macroscopic invertebrates in resin began in the Early Cretaceous, with only one record of this known before then (Schmidt et al., 2012). This probably explains why the start of the oniscidean fossil record is only known from Early Cretaceous amber (Aptian-Cenomanian) while a Carboniferous origin of this group is assumed (Broly et al., 2013). To our knowledge, Cretaceous amber with woodlice inclusions is only known from three countries * Corresponding authors. E-mail addresses: pierre.broly@icl-lille.fr (P. Broly), a.ross@nms.ac.uk (A.J. Ross). Contents lists available at ScienceDirect Cretaceous Research journal homepage: www.elsevier.com/locate/CretRes http://dx.doi.org/10.1016/j.cretres.2015.02.012 0195-6671/© 2015 Elsevier Ltd. All rights reserved. Cretaceous Research 55 (2015) 220e228