The Pyraloidea of Eungella: a Moth Fauna in Its Elevational and Distributional Context
Total Page：16
File Type：pdf, Size：1020Kb
THE PYRALOIDEA OF EUNGELLA: A MOTH FAUNA IN ITS ELEVATIONAL AND DISTRIBUTIONAL CONTEXT KITCHING, R. L.1, ASHTON, L. A.1,2, ORR, A. G.1 & ODELL, E. H.1 An intensive, two-season survey of moths along an elevational transect from 200 to 1200 m above sea level was an integral part of the recent Eungella biodiversity survey. The overall results have been published elsewhere. In this paper we examine in finer detail the patterns of distribution and faun istics of one of the dominant taxa from that dataset. The Pyraloidea comprise two families of so-called micro-moths, the Pyralidae and the Crambidae. Overall we sampled more than 7000 indi- viduals of more than 100 species. In spring these were principally in the lowland sites, but the summer samples were more evenly spread across elevations. In both seasons characteristic upland and lowland assemblages were apparent, separating at about 700 m above sea level. These elevational patterns were driven statistically by a small group of abundant species. Focusing on the Pyraustinae-Spilomelinae clade (91 species in our samples) and comparing them with samples from other Australian rainforest locations suggests that the Eungella forests represent the southernmost limits for 24 species, and the northern limits for five species. In other cases, the species is known from sites both north and south of Eungella. Keywords: Pyraloidea, Spilomelinae/Pyraustinae, Eungella, elevation, distribution 1 Environmental Futures Research Institute, Griffith University, Nathan, Queensland, Australia ([email protected]) 2 School of Biological Sciences, University of Hong Kong, Pokfulam, Hong Kong, China INTRODUCTION clear demarcation between moth ass emblages at 800 m The Lepidoptera, the butterflies and moths, are pre- above sea level and higher, compared with those at dominantly herbivorous and, within all ‘green’ eco- lower elevations (see ‘Methods’ below) for both spring systems, play an important role in connecting the (November) and late summer (March) samples. The primary producing plants to the superimposed animal samples collected over two seasons were dominated by food-web, principally through the consuming activ ities four groups of species within the Order – the families of their larvae. Estimates vary, but there may be close Erebidae, Geometridae and Noctuidae, together with the to a million species within the Order, most of which superfamily Pyraloidea. Together, these four taxa (com- are night-flying moths. As a group, the moths are ideal prising five families) made up 65% of the spring samples for comparative studies that aim to examine changes in and 76% of the late summer catches. In each case the community structure across ecological gradients such Pyraloidea, viz. the families Crambidae and Pyralidae, as latitude or elevation. The moths are highly speciose were was the most abundant taxon in both seasons (26% in most locations; are readily sampled using light traps; of all moths collected in spring, 35% in late summer) and are relatively well known taxonomically (although (Figures calculated from Odell et al.’s (2016) Table 2). large gaps in our knowledge remain). The Odell et al. (2016) analysis further nomi- For all of these reasons, they were one of the focal nated ‘indicator species’ based on an IndVal analysis groups targeted in the recent Eungella biodiversity (Dufrene & Legendre, 1997) which identifies species survey (Ashton et al., this volume). Specifically, we that are both restricted to and occur consistently sampled all moths with a forewing length of 1 cm or within particular elevational bands. Of particular more, plus additional smaller members of selected interest in the present context was the identification of families (including the Crambidae and Pyralidae). An nine species of Pyraloidea among the 23 species’ ‘pre- analysis of the results for this entire fauna has been dictor set’ (sensu Kitching & Ashton, 2013) across the presented by Odell et al. (2016). These authors found a two seasons sampled. 65 66 PROCEEDINGS OF THE ROYAL SOCIETY OF QUEENSLAND For these reasons as well as their intrinsic ecological In this treatment, then, we address four inter- interest, we have chosen to analyse the catches of Pyra- related questions. loidea (Pyralidae and Crambidae) in more detail in this • Do members of the Pyraloidea from the Eungella paper. We further compare the species distributions of rainforests form elevation-specific assemblages two of the major subfamilies within the Crambidae and, if so, do these reflect the patterns shown by (Pyraustinae and Spilomelinae) against simi lar samples the moth fauna as a whole? collected by us over seven other north-eastern Aust ra- • Are there seasonal differences in elevational lian rainforest localities. patterns shown by the Pyraloidea? The Pyraloidea represent one of the largest groups • If there is elevational partitioning, which species within the Lepidoptera. Globally, many species remain are best correlated with the observed patterns? undescribed and many of the larger genera are in need • How widespread beyond Eungella are mem- of revision. Nevertheless, Munroe & Solis (1999) esti- bers of the dominant subfamilies Pyraustinae mated that there were 16,000 described species and at and Spilomelinae (the ‘PS clade’) which were least as many awaiting attention. These authors also encountered? confirmed the two subsumed taxa, the Pyralidae and the Crambidae, as full families (following Minet, 1982). METHODS In Australia, and based on the most recent checklists The Eungella Biodiversity Survey (Neilsen, Edwards & Rangsi, 1996; https://bio diversity. Details of the study sites and sampling methods have org.au/afd/mainchecklist), the described species within already been presented by Odell et al. (2016), and fur- the superfamily represent somewhat more than 1200 ther detail is provided in companion papers (Ashton species (ca 480 of Pyralidae and ca 770 of Crambidae. et al., this volume). Accordingly, summaries only are This establishes the Pyraloidea as one of the more provided here. The two aforementioned works also speciose superfamilies in the Aus tralian lepidopter- contain maps of the sampling sites. ous fauna. Conventionally designated by collectors as ‘micro’-moths, the pyraloids in general are relatively Eungella National Park large as adults (at least compared with other ‘micros’ All study sites were located within the rainforest – although some minute forms are placed within the sections of Eungella National Park (21°S, 148°E) superfamily). The taxon contains some species of con- and Pelion State Forest located on the Clarke Range siderable economic importance, including the notorious some 80 km west of Mackay in central Queensland. wax-moth (Galleria mellonella), a pest of beehives; the Four study plots were established within each of six flour moth Pyralis( farinalis), a pest of stored grain; as elevational bands – at 200 m, 400 m, 600 m, 800 m, well as a wide range of forest and crop pests (lists in 1000 m and 1200 m above sea level. In each case, Common, 1990; Neilsen et al., 1996). the elevations of plots fell within ±50 m of the desig- In a recent multi-locus DNA-based phylogeny of nated band. Plots were a minimum of 500 m apart. the superfamily, Regier et al. (2012) provided evidence The physical environment of the region and the plots for five subfamilies within the Pyralidae s.s.( ) and is summarised by Ashton et al. (this volume). A 20 × twelve putatively monophyletic subfamilies within the 20 m vegetation reference plot was established at each Crambidae. Within the Crambidae, their placing of the location, and results from these surveys are in Ashton Schoenobiinae suggests this sub family is paraphyletic, et al. (this volume). associated with the Acentrotinae. Their analyses did not include material from the Cymbalomiinae. In the Sampling at Eungella present context they identified the two sub families, the On two occasions (November 2013 and March 2014), Pyr aus tinae and the Spilomelinae (designated as the moths were sampled at Eungella using Pennsylvania- single subfamily Pyraustinae (s.l.) by Common (1990) style light traps modified for use in rainforest con- and other earlier authors), as forming a clear isolated ditions (Kitching et al., 2005). These traps comprise clade which they refer to as the ‘PS clade’, which also a vertically placed UV-dominant fluorescent tube contains the previously recognised, aberrant sub family, powered by a 12-volt battery and surrounded by three the Wurthiinae. This clade is sister to all the other transparent Perspex vanes. Moths attracted to the Crambidae. This is significant here because we have light are knocked down by the vanes and collected in chosen this clade, by far the most speciose within the a bucket suspended beneath. At each location, traps superfamily, for more detailed analysis (see below). were hung at both head height and in the canopy THE PYRALOIDEA OF EUNGELLA: A MOTH FAUNA IN ITS ELEVATIONAL 67 AND DISTRIBUTIONAL CONTEXT above (after ropes had been suspended there with the one-hectare reference plot was established adjacent aid of a bow and line-throwing arrows). Traps were to the site of the canopy crane facility in 2000. The open all night for three, usually consecutive, nights vegetation of this site was described by Laidlaw et al. at each location. Ground and canopy were sampled (2007). Four light traps were run for four nights within simultaneously at each location. All moths with a the one hectare during this survey. Considerably later, forewing length greater than 1 cm were removed from the canopy crane site itself was the location for a the catches each day and sorted to ‘morphospecies’ vertically stratified survey in which five traps were (i.e. ‘species’ that exhibited repeatedly recognisable disposed at 10 m vertical intervals over a three-week appearances). In the case of the readily recognis- period on two occasions (January and July 2012). able Pyraloidea, any smaller individuals within the Moth data from this survey remain unpublished, but samples were also removed and sorted.