FIRST RECORDS OF MIRACYTHERE HORNIBROOK, 1952 (CRUSTACEA, 
OSTRACODA) FROM THE TERTIARY OF AUSTRALIA 
J. V. Neil 
Department of Geology, University of Melbourne, Parkvillc, Victoria 3052 
Present address: 23 Michael Street, Bendigo, Victoria 3550 
Neil, J. V., 1991:12:31. First records of Miracythere Hornibrook, 1952 (Crustacea, Ostra- 
coda) from the Tertiary of Australia. Proceedings of the Royal Society of Victoria 103 
(2): 87-92. ISSN 0035-921 1. 
A new species of the rare ostracode genus Miracythere Hornibrook, 1952, previously 
known only from New Zealand, is described from late Early or early Middle Miocene 
(Batesfordian) strata of the Muddy Creek Formation near Hamilton, southwestern Victoria. 
The new species is not formally named because the only complete adult valve amongst the 
limited material discovered has been lost. A specimen of another undescribed species poss¬ 
ibly belonging to Miracythere is also figured from the Late Eocene of South Australia. The 
literature relating to this genus is reviewed, and the morphological parallels between Mira¬ 
cythere and some Palaeozoic genera are briefly discussed. 
MIRACYTHERE is a rare and distinctive ostra¬ 
code genus erected by Hornibrook (1952) for his 
new species M. novaspecta from dredgings off 
the northern tip of New Zealand. He indicated 
that the type species is widely distributed in New 
Zealand waters, though no locality data were 
given. No other species of the genus has been 
described, and the only other documented oc¬ 
currence of M. novaspecta has been two valves 
recorded from the Otago Shelf by Swanson 
(1979a). 
Hornibrook (1952, 1968) gave the strati¬ 
graphic range of Miracythere as Late Eocene 
(Runangan) to Recent and of M. novaspecta as 
Early Miocene (Hutchinsonian) to Recent, but 
he did not record any fossil occurrences. He has 
recently informed me (written communication 
1985) that the Eocene occurrence cannot be con¬ 
firmed, but that a specimen of M. novaspecta is 
known from the Wharekuri Greensand of Late 
Oligocene (Duntroonian) age, at a locality on the 
Waitaki River in the South Island now sub¬ 
merged by a hydroelectricity scheme reservoir. 
That occurrence, and a broken specimen (Fig. 
IB) oil Miracythere that I have recovered from 
the Tuketja Member of the Blanche Point For¬ 
mation of South Australia (Late Eocene; Jenkins 
et al. 1982), predate the Victorian species de¬ 
scribed in the present paper. I have also picked a 
specimen of another undescribed species of 
^Miracythere from a sample supplied by Dr B. 
Hayward from the Pleistocene (Castlecliffian 
Stage) Wanganui Series of New Zealand (Fig. 
-Q. No other occurrences of the genus are 
known at present. 
SYSTEMATIC PALAEONTOLOGY 
Family Bythocytheridae Sars, 1866 
Remarks. Hornibrook (1952) placed Mira¬ 
cythere in the Bythocytherinae but noted that 
the hinge, with a posterior tooth in the left valve, 
is more complex than the characteristic bythocy- 
therinid hinge. Schornikov (1981) regarded the 
genus as Bythocytherinae incertae sedis. Since I 
follow Hartmann & Puri (1974) in not recognis¬ 
ing subfamilial groupings within the Bythocy¬ 
theridae, the question of the placement of 
Miracythere at the subfamilial level does not 
arise. The hinge type as diagnosed by Horni¬ 
brook, and its variation in the Victorian species 
described here, fall within the range accepted as 
“normal” for bythocytherids. 
Genus Miracythere Hornibrook, 1952 
Type species. Miracythere novaspecta Hornibrook, 
1952. 
Diagnosis. See Hornibrook 1952: 61-62. 
Remarks. A specimen from the Gulf of Cali¬ 
fornia and another of Cretaceous age from a 
deep sea drilling core in the Shatsky Rise, 
northwestern Pacific Ocean (DSDP 6-48.2) were 
tentatively assigned to Miracythere by Swain 
(1967; in Maddocks 1983). Both specimens dif¬ 
fer from M. novaspecta in lacking a median 
sulcus, being longer, being caudate rather than 
subquadrate, and in having reticulate rather 
than smooth-surfaced valves. These differences 
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