Bull. nat. Hist. Mus. Lond. (Zool.) 68(1): 39-50 
1S eS Saar 
Issued 27 June 2002 

A new genus of groundwater Ameiridae 
(Copepoda, Harpacticoida) from boreholes in 
Western Australia and the artificial status of 
Stygonitocrella Petkovski, 1976 

WONCHOEL LEE 
Department of Life Sciences, College of Natural Sciences, Hanyang University, Seoul 133-791, Korea; e-mail: 
wlee @ hanyang.ac.kr 
RONY HUYS* 
Department of Zoology, The Natural History Museum, Cromwell Road, London SW7 SBD, U.K.; e-mail: 
rjh@nhm.ac.uk 

SYNOPSIS. Examination of the copepod fauna inhabiting 50m deep production bores on Barrow Island (northwestern 
Australia), resulted in the discovery of an unusual ameirid which cannot be placed in any extant genus. Both sexes are 
characterized by a unisetose antennary exopod and extreme reduction in the swimming legs (particularly the endopods) and PS. 
Males lack a defined P6 closing off the single genital aperture and have an extraordinarily large spermatophore. Females similarly 
display a highly reduced genital field. 
The new species shows superficial similarities to both Psammonitocrella Rouch and Stygonitocrella Reid, Hunt & Stanley, 
however the combined presence of a sexually dimorphic inner basal spine on P1, a completely fused genital double-somite, 
reduced antennary exopod and vestigial PS excludes it from either genus. Some problems in the current classification of 
freshwater Ameiridae are highlighted, with particular reference to the genus Stygonitocrella. A new genus Neonitocrella is 
proposed for Stygonitocrella insularis (Miura, 1962). 
INTRODUCTION 
The arid to semi-arid north-west of Western Australia has a rich 
stygofauna including the only vertebrate troglobites known to occur 
in Australasia, the Blind Gudgeon, Milyeringa veritas Whitley, and 
the Cave Eel, Ophisternon candidum (Mees), and two, supposedly 
sympatric, congeneric shrimps, Stygiocaris lancifera Holthuis and 
S. stylifera Holthuis with tethyan affinities (Humphreys, 1993). 
Recently, the freshwater copepods of the Cape Range karst area 
have been the subject of intensive study, resulting in the discovery 
and description of several cyclopoids belonging to the genera 
Metacyclops Kiefer, Mesocyclops Sars, Microcyclops Claus, 
Apocyclops Lindberg, Diacyclops Kiefer and Halicyclops Norman 
(Pesce et al., 1996a—b; Pesce & De Laurentiis, 1996; De Laurentiis 
et al., 1999). 
Here we report on the discovery of a remarkable harpacticoid in 
abandoned production bore holes on Barrow Island off the Cape 
Range coast. Barrow Island has a typical island Ghyben-Herzberg 
system with a freshwater lens overlying salt water. The hydrology of 
the superficial karst is little known despite being a production oil 
field since the early 1960s and being the target of ‘produced water’ 
disposal until recently. It lies on the North West Shelf of Western 
Australia and up to about 8—10,000 years ago it would have been 
part of the mainland (and throughout most of the last few million 
years) (Humphreys, 2000). The entire island is likely to be an 
anchialine system but to date an entry point for divers has not been 
* Author for correspondence 
© The Natural History Museum, 2002 
found yet. The subterranean fauna contains Thermosbaenacea, 
Syncarida and a diverse amphipod community including bogidiellids 
and melitids. Our samples were taken in a long abandoned water 
production bore (47 m depth) and an abandoned anode bore (55 m 
depth) that was used in the electrolytic protection of the oil wells. 
The latter would have gassed chlorine and had a pH of <2 when in 
service (Humphreys, pers. comm). 
MATERIALS AND METHODS 
Specimens were dissected in lactic acid and the dissected parts were 
mounted on slides in lactophenol mounting medium. Preparations 
were sealed with Glyceel or transparent nail varnish. All drawings 
have been prepared using a camera lucida on a Zeiss Axioskop 
differential interference contrast microscope. 
Males and females of Jnermipes humphreysi gen et sp. noy. were 
examined with a Philips XL30 scanning electron microscope. Speci- 
mens were prepared by dehydration through graded acetone, critical 
point dried, mounted on stubs and sputter-coated with gold or 
palladium. 
The descriptive terminology is adopted from Huys et al. (1996). 
Abbreviations used in the text are: ae, aesthetasc; P1—P6, first to 
sixth thoracopod; exp(enp)-1(2, 3) to denote the proximal (middle, 
distal) segment of a ramus. Type material is deposited in the 
collections of the Western Australian Museum, Perth (WAM) and 
The Natural History Museum, London (BMNH). 
