30 
W.F. Humphreys, M.N. Feinberg 
the prey species ( Stygiocaris spp.) have been listed 
under Schedule One of the Wildlife Protection Act 
of Western Australia owing to their small 
geographic distribution, low populations and 
vulnerability of their habitat. 
To establish basic biological data required for 
conservation purposes the gut contents of existing 
collections have been examined to elucidate their 
prey. 
METHODS 
The intestines were either dissected out and later 
examined by flushing the contents, or the flushing 
was conducted in situ on intestines longitudinally 
incised. The contents were identified to whatever 
level practicable depending on the state of 
digestion. As no details are available of the 
treatment of the specimens prior to preservation, 
no attempt is made to quantify feeding rates. 
With the exception of the holotype the gut 
contents were examined of all available specimens 
of Ophistemon candidum namely, Paratype P4918 
Tantabiddy Well (C-26), Yardie Creek Station, 
collected A.M. Douglas and G.F. Mees, 17/5/1960; 
P5813; Tantabiddy Well (C-26), Yardie Creek 
Station, collected A.M. Douglas, 22/7/1963; P7716; 
North West Cape area, collected R. Gredling, 1963- 
4. 
The stomach contents of a large series of 
Milyeringa veritas in the collection of the American 
Museum of Natural History were extracted by 
MNF and examined in Perth. Material came from: 
AMNH 45497 (N=30) which included specimens 
collected by Nelson, Butler and Rosen from the 
west side of the Cape Range peninsula between 
Yardie Station and Yardie Creek on the afternoon 
of 2 April 1969; AMNH 48568 (N=20) which 
included specimens collected by Nelson, Butler 
and Rosen from the east side of Cape Range 
peninsula from Neds Well to Mowbowra Creek on 
the morning of 5 April 1969. 
RESULTS AND DISCUSSION 
Ophistemon candidum 
Members of the stygofauna were found in the 
midgut of P5813, namely thermosbaenaceans 
(Halosbaena tulki Poore and Humphreys, 1992) and 
atyid shrimps ( Stygiocaris sp.); sand grains to 1.2 
mm diameter were also recovered. The hindgut of 
the same individual yielded only terrestrial taxa or 
taxa terrestrial as adults namely, slaters (Isopoda: 
Philosciidae) and dragonfly (Odonata) and 
dipteran larvae (Table 1). No gut contents were 
found in P4918 or P7716. 
The gut contents and the habitat characteristics 
of the taxa would suggest that two feeding 
episodes had occurred in the first (hindgut) of 
which the eel foraged in an open cave habitat on a 
non-cave aquatic fauna (Odonata and Diptera 
larvae) as well as cryptic species accidentally in the 
water (philosciid isopod). During the subsequent 
feeding episode the eel foraged solely on the 
specialised subterranean aquatic (stygo-) fauna 
comprising sediment foraging species ( Halosbaem 
and Stygiocaris). 
No shrimps were taken from Tantabiddy Well 
(C-26) in the original collections (Mees 1962) or 
subsequently (Humphreys and Adams 1991; W.F. 
Humphreys, unpublished) although both S. 
lancifera and S. stylifera occur in an adjacent well 
(C-25, Kudamurra Well; Mees 1962; W.F. 
Humphreys and M. Adams, unpublished 1991). 
Halosbaena has not been collected from C-26 (Poore 
and Humphreys 1992; W.F. Humphreys, 
unpublished). Hence, these gut contents constitute 
the only records of Stygiocaris and Halosbaena from 
C-26. 
The distribution of the genus Ophistemon has 
been described as Gondwanan (Rosen and 
Greenwood 1976) but a recent interpretation 
considered both the genus Ophistemon and the 
family Synbranchidae to have a Tethyan 
distribution (Banarescu 1990: 203). The latter 
interpretation would accord with the stygofauna of 
Table 1 The gut contents of Ophistemon candidum in the collections of the Western Australian Museum. 
Location 
Identification 
Reg. No. 
Midgut 
Thermosbaenacea, Halosbaena tulki 
BES: 820 
Midgut 
Atyidae: Stygiocaris sp. 
BES: 821 
Midgut 
Atyidae: Stygiocaris sp. 
BES: 822 
Midgut 
Thermosbaenacea, Halosbaena tulki 
BES: 823 
Midgut 
Thermosbaenacea, Halosbaena tulki 
BES: 824 
Midgut 
Thermosbaenacea, Halosbaena tulki 
BES: 825 
Midgut 
Sand to 1.2 mm diameter and residue 
BES: 826 
Hindgut 
Isopoda: Philosciidae 
BES: 817 
Hindgut 
Odonata, larva 
BES: 818 
Hindgut 
Unidentified 
BES: 819 
Hindgut 
Diptera, larva 
BES: 856 
