87 (3) · December 2015 pp. 169–181 A new Australian species of Acrotelsella (Zygentoma: Lepismatidae); could it be an endangered short range endemic? Graeme Smith Australian Museum, 6 College Street, Sydney, New South Wales 2010, Australia and Federation University Australia, PO Box 663, Ballarat, Victoria 3353, Australia E-mail: [email protected] Received 1 December 2014 | Accepted 15 July 2015 Published online at www.soil-organisms.de 1 December 2015 | Printed version 15 December 2015 Abstract A new and comparatively attractive species of silverfish from the genusAcrotelsella is described from specimens collected near the summit of a mountain in central Australia. It is unusual in displaying medial combs on some urosternites. Questions are posed as to whether it is a species with a very restricted range that may be endangered by global warming, or simply a reflection of the poor state of knowledge of the Australian silverfish fauna. Keywords Thysanura | taxonomy | new species | global warming 1. Introduction a synonym of Stylifera until further evidence was available. This suggestion was followed by Paclt (1967), Escherich (1905) erected the genus Acrotelsa for who placed Acrotelsella as a subgenus within Stylifera all species of Lepismatidae with an acutely triangular in his catalogue of the Lepismatidae. Mendes (1982), in urotergite X. He nominated the circumtropical species his unpublished review of the Lepismatidae, considered Lepisma collaris Fabricius, 1793 as the type species Acrotelsella to be a genus independent of Stylifera, and described three new species including Acrotelsa the same position being accepted by Irish (1988) in his producta Escherich, 1905, which was the first silverfish revision of the genus Stylifera and that which is followed species to be described from Australia. Silvestri (1935) here. split Acrotelsa into three genera without explanation, Eighteen species (or subspecies) of Acrotelsella have nominating Acrotelsa producta as the type species been described to date. Seven of these species were of his new genus Acrotelsella. He seems to have been collected in the drier regions of Australia, the rest unaware of Stach (1932), who also split Acrotelsa into in Southeast Asia, China, Somalia, Yemen, Kenya, two subgenera, with Acrotelsa (Stylifera) containing Colombia, the Seychelles, Hawaii and French Polynesia. only the neotropical species A. galapagoensis (Banks, This paper describes a new, quite different and 1901) from the Galapagos Islands and A. gigantea comparatively attractive species (Fig. 1) collected under Escherich, 1905 from the Antilles. Wygodzinsky (1959) rocks about 200 metres below the summit of Mt Sonder raised Stylifera to the level of genus and suggested (or Rwetyepme - its aboriginal name), 1380 m in altitude, that Acrotelsella Silvestri, 1935 should be considered located in the centre of Australia (Figs 2, 3). © Senckenberg Museum of Natural History Görlitz · 2015 ISSN 1864-6417 170 Graeme Smith 2. Materials and methods 3. Systematics Type specimens were collected within a few metres Family Lepismatidae Latreille, 1802 of each other. Locality co-ordinates for specimens were obtained using a hand held Garmin eTrex®10 GPS with a Subfamily Ctenolepismatinae Mendes, claimed accuracy usually under five metres. All specimens 1991 were initially stored in 75–80 % ethanol. Acrotelsella Silvestri, 1935: 307. Methods for measurement and dissection are the same as described in Smith (2013). The female holotype and Acrotelsa Escherich, 1905 (pro parte): 105. one male paratype (dissected and mounted on two slides Acrotelsa (Acrotelsa) Stach, 1932: 333. each) are deposited with the Northern Territory Museum of Acrotelsella Silvestri, 1935: 307. Arts and Sciences, Darwin, Australia and two paratypes in alcohol are with the Australian Museum, Sydney, Australia. Stylifera Wygodzinsky, 1959: 39. All climate data was taken from the Australian Bureau Stylifera (Acrotelsella) Paclt, 1967: 54. of Meteorology website on 24 June 2014 (http://www. bom.gov.au/climate/data/). Type species: Acrotelsa producta Escherich, 1905 by Roman numerals are used to indicate abdominal original designation. segment number. In addition the following abbreviations are used: asl: above sea level (in metres); HW: head width (in millimetres); H+B: head and body length Acrotelsella erniei n. sp. (Figs 1, 4–50) (in millimetres); L/W: length to width (ratio); PI, PII, PIII: legs of prothorax, mesothorax and metathorax, Material examined. Australia, Northern Territory: West respectively. The term macrochaetae refers to the larger MacDonnell National Park, Mount Sonder track near summit stronger bristles (generally pectinate in this species); setae 23°34.711‘S 132°34.100‘ E, 1194 m asl, 10.vii.2009, Graeme Smith. refers to smaller thinner bristles (always simple); setulae holotype ♀ (HW 1.10) (NTM I009249) on two slides; paratypes ♂ (HW 1.25) (NTM I009250) on two slides, ♂ (HW 1.01) (K377609) to the very small, usually straight setae associated with in alcohol, ♀ (HW 0.99) (K377610) in alcohol. All specimens with the combs and cilia to the curly thin hairs, often associated same collection data as holotype. with the combs, setal collar or notal margins. Figure 1. Acrotelsella erniei n.sp SOIL ORGANISMS 87 (3) 2015 New Acrotelsella from central Australia 171 Diagnosis. Its colour and scale pattern when alive and thorax only slightly wider than abdominal segment I, the presence of medial combs on some of the urosternites the following abdominal segments about the same width distinguishes this species from all other described species until the fourth or fifth from, where it narrows moderately of Acrotelsella, as well as the many other undescribed towards the posterior end; the large coxae quite visible at Australian species seen by the author. the sides of the body. Pigment generally absent, except Description. Appearance in life mottled grey with for the antennae and terminal filaments which are evenly distinct lighter posterior margins to all tergites, legs light brown. almost white, antennae and terminal filaments light Scales (Fig. 5) unevenly rounded, ovoid, distally brown (Fig. 1). truncate or even somewhat irregular with notches in the Body length up to 8.3 mm (♀), 9.3 (♂); maximum head distal margin, with numerous light brown parallel ribs that width 1.25 mm; thorax: length up to 2.8 mm (or 0.30–0.32 do not extend beyond the margin. Scales on appendages, times H+B); width up to 1.80 mm with no great difference ventral surface and along margins of tergites with grey between the pro-, meso- and metanota, although the or hyaline ribs (in alcohol). Macrochaetae hyaline and mesonotum is the widest; antennae incomplete in all mostly pectinate (Fig. 6). specimens, maximum preserved length of antenna 5.5 Head (Fig. 7) wider than long with scales dorsally. mm (or 0.5–0.62 H+B); maximum length of intact cercus Macrochaetae prominent in two bushes on the antero- 3.95 mm (or 0.48 H+B); median dorsal appendage broken lateral corners, each consisting of about seven curved in all specimens, maximum preserved length 2.65 mm or rows; slightly posterior to the antennal base, these bushes 0.32 H+B. Body neither elongate nor broad (Fig. 4) with almost join with the marginal rows about two to three Figure 2. Collection locality, Mt. Sonder. SOIL ORGANISMS 87 (3) 2015 172 Graeme Smith macrochaetae wide running along the sides of the head well-developed molar and incisor areas; a group of about to the level of the eyes and then running above the eyes. nine strong apically bifurcated but otherwise simple setae On each side of the head, there is also a small group distally adjacent to the pectinate molar area and a bush of of macrochaetae posterior to the antennal base which setae and macrochaetae externally. Maxilla (Figs 12, 13) includes a long thin seta. Eyes dark brown. Clypeus with with three pectinate macrochaetae externally proximal to 1+1 bushes consisting of tightly grouped macrochaetae the palp, the lacinia with three strong teeth, one shorter as well as some small setae posterolaterally. Labrum than the rest, followed by six or seven lamellate processes also with 1+1 bushes of tightly grouped macrochaetae and a row of seven or eight apically bifurcate setae. as well as many simple setae and two longer thin setae. Apical article of maxillary palp 2.6–3.6 times longer than Antennae incomplete in all specimens but fairly long, wide and 1.0–1.3 times longer than penultimate article; reaching a little under two thirds H+B. Scape (Fig. 8) the ultimate article in both sexes without any obvious quite long with short robust simple setae apically and papillae or specialised sensillae. Last three articles of palp hyaline scales. Pedicel covered with numerous finer setae with fine setae; basal and second articles with subapical and some cilia; subsequent articles with single rosette coronae of slightly thicker setae. Hyaline scales present of setae transversely across the middle of the article on second and probably third article of palp, probably and two short trichobothria per article (hidden behind absent from basal, fourth and fifth articles. Labium (Fig. flagellum in illustration), which decrease in frequency to 14) short and broad with rows of short strong apically every fourth subarticle distally as well as some additional bifurcated setae on the prementum. Postmentum with apical cilia. More apical articles (Fig. 9) with both rod- a transverse row of apically bifurcate setae, which are like and sausage-shaped basiconic sensilla near the apex shorter and stronger at the lateral margins. Glossae of each article; the more distal subarticles of each article and paraglossae quite broad with short curved setulae. with trichobothria, which progressively become very Labial palp short; apical article suboval expanded slightly short (eventually not much longer than the fine subapical medially (Fig. 15), wider than or as wide as long (L/W setae). Mandibles (Figs 10, 11) typical for genus with 0.7–1.0), with five papillae of compact type arranged in Figure 3.