Thirteen new charopid land snails from mid-eastern Queensland rainforests (Gastropoda: Eupulmonata: Charopidae)

Abstract

Thirteen new species of charopid land snail are described from mid-eastern Queensland rainforests. These are assigned to four newly diagnosed genera: Hirsutaropa sarina gen. et sp. nov., Burwellia staceythomsonae gen. et sp. nov., Albiropa microscopica gen. et sp. nov., Eungellaropa crediton gen. et sp. nov. and six existing genera: Lenwebbia marissae sp.nov., Omphaloropa subvaricosa sp. nov., Amfractaropa southpercyensis sp. nov., Comularopa wendyae sp. nov., Isolderopa gloucester sp. nov., Tristanoropa southmolle sp. nov., Tristanoropa summerae sp. nov., Tristanoropa jaxut sp. nov. and Tristanoropa hazelwood sp. nov. An additional six species are recognised formally but not formally described due to poor quality material. New distribution data is presented for Setomedea janae Stanisic, 1990, Discocharopa aperta (Möllendorff, 1888) and Sinployea intensa Iredale, 1941. The latter two represent new records for mid-eastern Queensland. A short discussion on the potential implications of the expanded MEQ charopid fauna for east coast biogeography is presented.  Gastropoda, Eupulmonata, Charopidae, new genera, new species, mid-eastern Queensland. Holcroft, L. & Stanisic, J. 156 Memoirs of the Queensland Museum | Nature  2018  61 MEQ but several species were collected from off-lying islands which in fairly recent times (approximately 15 000 ybp) were connected to the mainland. Many of the putative new species (14) have been formally described in two systematic papers which also revised existing species (Holcroft 2018c, d). In this paper we describe an additional thirteen species of MEQ Charopidae recorded by Holcroft (2018b) including some which were concealed among ‘material examined’ lists of more broadly defined species in that study. These new species are allocated to four newly diagnosed and six existing genera. We also present additional distribution data for three previously described species occurring in the region: Setomedea janae Stanisic, 1990, Discocharopa aperta (Möllendorff, 1888) and Sinployea intensa (Iredale, 1941). The latter two are new records for MEQ. A further six species are identified as putatively new from material listed in Holcroft (2018b) but are not formally described at this time because of poor quality material or material damaged during specimen preparation and handling. These damaged shells and fragments are documented and illustrated with brief accompanying remarks, not only to complete the species inventory, but more so to encourage and direct future investigations. MATERIALS AND METHODS The study is based on material revised in Holcroft (2018b). Individual specimens are identified by their registration number and respective institutional prefix (QMMO, Queensland Museum; AMSC, Australian Museum). Species not formally described are denoted by a family descriptor and alphanumeric codon that is used in both the QM’s and AM’s land snail databases to denote undescribed land snail species, e.g. Charopid MQ 43. Investigations of shell characters were carried out on specimens in the museums’ dry collections (denoted as RC) by Holcroft and are presented in detail in Holcroft (2018b). Spirit specimens are denoted SC. Characters scored included shell height and diameter, whorl count, rib count on the first whorl and umbilical width. Whorl counts were made to the nearest 1/8 whorl using the methodology of Solem (1983). Specimens were studied using a WILD M5 stereo microscope and shell photographs were taken using a NIKON 4200 Coolpix camera with microscope attachment. High resolution images of shells (260-600MB) were obtained using a Visionary Digital BK-Plus lab system camera set-up located in the Queensland Museum’s Digital Imaging Unit. Shell sculpture was investigated and photographed using a TM1000 Tabletop Scanning Electron Microscope at the Queensland Museum. Shells were cleaned in an ultrasonic cleaner and not by chemical means in order to prevent the removal of the periostracum which shows many of the shell’s sculptural elements. Shells used in the study were mostly recovered from leaf litter and occasionally were extremely fragile. In some cases the cleaning process and subsequent handling led to shell damage, some severe with only an illustration as evidence of the shell’s morphology and its existence in MEQ. Abbreviations used: General: SEM, scanning electron microscopy; SC, spirit collection; RC, dry collection. Institutions: AM, Australian Museum, Sydney; QM, Queensland Museum, Brisbane. Habitat Data: alt, altitude; Ck, Creek; CMC, Central Mackay Coast; cnvf, complex notophyll vine forest; Hts, Heights; I., Island; Mts, Mountains; nvf, notophyll vine forest; R, River; Ra, Range; sevt, semi-evergreen vine thicket; MEQ, Mid-eastern Queensland; NP, National Park; NSW, New South Wales; NENSW, North-eastern New South Wales; NEQ, North-eastern Queensland; SEQ, Southeastern Queensland; SF, State Forest; WT, Wet Tropics. Generic differentiation and species delimitation Holcroft (2018a) established a framework for using protoconch sculpture as a means of recognising putative genera in the absence of soft Thirteen new charopid land snails Memoirs of the Queensland Museum | Nature  2018  61 157 parts for the study of reproductive structures and DNA analyses. Through the examination of the protoconch sculptures of 186 eastern Australian charopids (described and undescribed) by scanning electron microscopy her study concluded that this embryonic shell feature could provide a more reliable generic signature for members of the family than earlier ad hoc attempts had done (e.g., Iredale 1933, 1937, 1941a, b). This conclusion largely reflected the results of the most recent and only molecularbased study of eastern Australian charopids which showed a strong connection between protoconch sculptural pattern and DNAbased generic-level clades (Shea et al. 2012). Thus new genera are diagnosed herein primarily on protoconch sculpture that is considered to be distinctive and differs from the sculptural patterns documented in previous studies (Stanisic 1990, Hyman & Stanisic 2005, Shea et al. 2012, Stanisic 2016, Holcroft 2018c, d). General shell features such as teleoconch sculpture and coiling pattern may also be important secondary considerations in generic determinations. New species are diagnosed on the basis of protoconch sculpture combined primarily with coiling pattern, shell shape and teleoconch sculpture.