Accepted by C. Lamas: 26 Sept. 2018; published: 14 Nov. 2018| Licensed under a Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0 ZOOTAXA ISSN 1175-5326 (print edition) ISSN 1175-5334 (online edition) Copyright © 2018 See end page footer Zootaxa 4521 (2): 287–293 http://www.mapress.com/j/zt/ Article 287 https://doi.org/10.11646/zootaxa.4521.2.10 http://zoobank.org/urn:lsid:zoobank.org:pub:E6E130FC-811D-4C91-8A42-786634108E17 Diversity of saproxylic dance flies and long-legged flies (Diptera: Empidoidea) in a temperate deciduous forest in Quebec, Canada JEFFREY M. CUMMING 1 , BRADLEY J. SINCLAIR 2 , SCOTT E. BROOKS 1 , JULIA MLYNAREK 3 & TERRY A. WHEELER † 1 Invertebrate Biodiversity, Agriculture and Agri-Food Canada, K.W. Neatby Bldg., C.E.F., 960 Carling Ave., Ottawa, ON, Canada K1A 0C6. E-mail: jeff.cumming@canada.ca, scott.brooks@canada.ca 2 Canadian National Collection of Insects and Ottawa Plant Laboratory—Entomology, CFIA, K.W. Neatby Bldg., C.E.F., 960 Carling Ave., Ottawa, ON, Canada K1A 0C6. E-mail: bradley.sinclair@canada.ca 3 Agriculture and Agri-Food Canada, Harrow Research and Development Centre, Harrow, ON, Canada N0R 1G0 E-mail: julia.mlynarek@canada.ca †Deceased, formerly with Department of Natural Resource Sciences, McGill University, Macdonald Campus, Ste-Anne-de-Bellevue, QC, Canada Abstract A large diversity of saproxylic Empidoidea from a temperate deciduous forest in southern Quebec is documented. Adults of 43 empidoid species representing 19 genera in 12 subfamilies and three families were collected from in situ sealed emergence traps placed over decayed logs of American beech (Fagus grandifolia Ehrhart) and sugar maple (Acer saccha- rum Marshall). The results of this technique give a clear indication of the saproxylic larval and pupal habitat of these spe- cies. The importance of Empidoidea as larval predators in decayed wood niches is noted. Key words: Dolichopodidae, Empididae, Hybotidae, emergence trap, American beech, sugar maple, larval habitat Introduction The Empidoidea are a large, diverse lineage of flies that include five to eight families depending on the classification scheme followed (e.g., Sinclair & Cumming 2006; Pape et al. 2011; Marshall 2012; Wahlberg & Johanson 2018). In terms of diversity the three largest families are the Dolichopodidae, Empididae and Hybotidae. As a group, adult Empidoidea are primarily predaceous flies, with many flower visiting taxa feeding on nectar or pollen (Ulrich 2005; Sinclair & Cumming 2006). However, the habits of immature Empidoidea are poorly known, with the larvae of a few groups (e.g., the empidid subfamilies Clinocerinae and Hemerodromiinae) being mainly aquatic (Dyte 1967), whereas most others are terrestrial, occurring in forests, grasslands and agricultural fields, or are associated with various semi-aquatic habitats (e.g., edges of ponds, bogs, marshes, fens, etc.) (Cumming & Sinclair 2008; Pollet & Brooks 2008). For recent summaries on what is known about immature Empidoidea, see Grichanov & Brooks (2017) for Dolichopodidae, Sinclair & Daugeron (2017) for Empididae, and Sinclair & Cumming (2017) for Hybotidae. In comparison with the aquatic empidoid groups, little has been published about the immature stages of the terrestrial groups, including their habits and the ecological niches they occupy. In general, terrestrial larvae are mainly considered to be predators of various arthropods in moist soils, with occasional additional records from other substrates such as dung, fungi, under bark, or in rotten wood (Dyte 1959; Smith 1989; Cumming & Cooper 1993; Meyer 2005). The prey items consumed by empidoid larvae are usually thought to be primarily larvae of other Diptera (Smith 1969; Cumming & Cooper 1993), but do vary depending upon habitat type (e.g., scolytid beetle larvae under bark preyed on by larvae of the dolichopodid genus Medetera Fischer von Waldheim) (Bickel 1985). Recently there has been considerable interest in the composition of saproxylic Diptera communities and their