Research Article |
Corresponding author: Abraham S.H. Breure ( bbreure@xs4all.nl ) Academic editor: Frank Köhler
© 2016 Corey S. Whisson, Abraham S.H. Breure.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Whisson CS, Breure ASH (2016) A new species of Bothriembryon (Mollusca, Gastropoda, Bothriembryontidae) from south-eastern Western Australia. ZooKeys 581: 127-140. https://doi.org/10.3897/zookeys.581.8044
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Bothriembryon sophiarum sp. n. is described, based on shell and anatomical morphology, from the coastal area of south-easternmost Western Australia. This is the first description of a new extant Australian bothriembryontid in 33 years. The shell of B. sophiarum is slender with a unique teleoconch sculpture. It is found in low coastal scrub on cliff edges and escarpments and because of its restricted distribution, qualifies as a short range endemic.
Western Australia, Orthalicoidea , ecology, anatomy, micro-CT
Along with the diverse and generally more northern and eastern Camaenidae, the endemic Australian genus Bothriembryon (Bothriembryontidae) forms a large and characteristic component of the Australian terrestrial molluscan fauna, particularly in Western Australia (
Recent taxonomic work on this group has been limited, with the last description of a new extant species being over thirty years ago (
A total of 22 lots comprising 242 specimens were examined from the malacological collection of the Western Australian Museum. Three relaxed formalin-fixed specimens were used for 3D visualisation (
Shell dimensions followed the methods figured by
Abbreviations of depositories:
Helix melo Quoy & Gaimard, 1832 by original designation
The use of subgenera within this genus is disputed.
Holotype. Western Australia, Nullabor Plain, Baxter Cliffs near Burnabbie Ruins, 32°07'30"S, 126°20'45"E, V. Kessner collector (ex J. Hemmen collection) 6 October 1989, dry,
Western Australia: Israelite Bay, W.G. Buick Collection No. 13096, Pre June 1992,
A slender shell characterised by plicate teleoconch whorls, often with pillared sculpture formed from incised spiral lines which become less frequent on the body whorl, and a strongly crenulate suture.
Shell morphology. Shell slender, mostly turriform, diameter 4.7–6.7 mm (mean 5.5 mm, sd 0.45), height 12.7–24.4 mm (mean 16.2 mm, sd 2.39) with 6.20–8.50 whorls (mean 7.05, sd 0.63) and a H/D ratio of 2.4–3.8 (mean 2.9, sd 0.26), rimate (Table
Shell measurements of the type material of Bothriembryon (B.) sophiarum sp. n.
B. (B.) sophiarum Registration number |
n | Shell height mm (sd) | Shell diameter mm (sd) | H/D Ratio (sd) | No. Whorls (range) |
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1 | 14.4 | 5.0 | 2.9 | 6.75 |
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2 | 12.7 (0) | 4.7 (0) | 2.7 (0) | 6.28 (6.20–6.35) |
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2 | 13.7 (0.35) | 5.0 (0) | 2.7 (0.07) | 6.48 (6.20–6.75) |
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6 | 15.3 (1.07) | 5.4 (0.30) | 2.8 (0.07) | 6.62 (6.25–7.00) |
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3 | 15.2 (0.06) | 5.4 (0.21) | 2.8 (0.12) | 6.57 (6.50–6.60) |
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1 | 16.2 | 5.7 | 2.8 | 6.85 |
Grand Mean | 15 | 14.7 (1.23) | 5.2 (0.35) | 2.8 (0.09) | 6.56 (6.20–7.00) |
Animal external morphology. Body and foot sculptured with regular honeycomb pattern. Upper body and tentacles dark brown to black with an olive to green foot base and sides, the latter relatively wide (Fig.
Distribution map of Bothriembryon (B.) sophiarum sp. n. (dot) including photo of holotype (
Genital morphology. (Based on micro-CT images, see Figs
Bothriembryon (B.) sophiarum sp. n.,
Bothriembryon (B.) sophiarum sp. n.,
Western Australia; along the escarpment and cliff tops of the Baxter Cliffs and Hampton Ranges from the Point Culver area eastward to the Burnabbie Ruins, a linear distance of about 180 kilometres (Fig.
Very open, low coastal scrub on limestone cliff-edge or slope scattered (often densely) with low limestone rocks and stones. Dominant plant species were Westringia dampieri, Correa backhouseana var. coriacea and Carpobrotus virens and very occasionally Melaleuca and Eucalyptus trees. In dry conditions living specimens are commonly found in rock crevices or fissures; under stones or around tree roots, and occasionally in litter. When wet, crawling snails have been observed on soil and stones and on branches of scrub (Fig.
Bothriembryon (Bothriembryon) sophiarum can be distinguished from most other Bothriembryon species by its shell morphology, notably its slender turriform shape and a teleoconch sculpture of coarsely plicate whorls and strongly crenulate sutures. Most Bothriembryon species are ovate to elongate-conical in shape and have a teleoconch sculpture of faint or narrow axial growth lines. The nearby Bothriembryon (B.) perditus Iredale, 1939 has similar shell morphology but its shell is much broader being elongate-conical in shape and has sutures which are more finely crenulate. The other nearby species Bothriembryon (B.) gratwicki (Cox, 1899) is similar in shape but its shell is broader and usually more elongated, with a coarse nodulose teleoconch sculpture (Fig.
Named in honour of Sophie Jade Whisson, first daughter of the senior author and Sophie J. Breure, spouse of the second author; noun in plural genitive case.
Bothriembryon (B.) sophiarum appears to have a restricted range with a linear distribution of ca. 180 km and as it currently occupies an area less than 10000 km2 qualifies as a Short Range Endemic (SRE) (
B. (B.) sophiarum has a slender, high-spired shell shape which is intriguing and differs from almost all known members of Bothriembryon which are predominantly ovate to elongate-conical in shape.
We would like to thank Alan Lymbery, Nerida Wilson, Shirley Slack-Smith and Lisa Kirkendale for comments on the manuscript. The senior author wishes to thank LK for her support and encouragement to the project. Ben Schneider and Andrew Cummings provided information, specimens and photographs. Alice Walker and Jonathan Ablett (NHM London) undertook part of the 3D scanning work. Ryonen Butcher and Rob Davis provided botanical identifications. The comments of Juan Francisco Araya and an anonymous reviewer on a previous draft helped to improve the manuscript. This publication was funded in part by a Research Training Scheme (RTS) grant to the senior author that forms part of a Masters of Philosophy (MPhil) degree at Murdoch University.
Bothriembryon (B.) sophiarum measurements of all material examined.
Data type: specimens measurements
Explanation note: See main text for abbreviations and methods used.