MILIOLIDAE - Acta Palaeontologica Polonica

22 EWA LUCZKOWSKA
Sigmoilina and Nummoloculina were found at 200 m. They are for the
most part small specimens (Moncharmont Zei, 1956). At depths from 180
to 315 m at Banco delle Vedove 32 species of miliolids were collected,
including numerous Quinqueloculina, Spiroloculina, Triloculina, Pyrgo
and Biloculinella (this last being considered to be characteristic of deep
water), which form 4 per cent of the population there (Moncharmont Zei,
1962). In the Gulf of Pozzuoli numerous Miliolidae and Elphidiidae occur
at 5 m and deeper to 110 m; there are large numbers of Quinqueloculina
and Pyrgo. Forms of the genus Quinqueloculina are particularly typical
of sandy and detritic deposits at 40 m (Moncharmont Zei, 1964). Off
Capri 17 miliolid species were found at 85 m, mostly those of the genus
Quinqueloculina (Cita, 1955).
In the Adriatic Sea the Miliolidae generally live in shallow off-shore
regions, e.g. abuI\dant Quinqueloculina at 37 m, Quinqueloculina, Triloculina
and Pyrgo at 166 m (Cita & Chierici, 1962); numerous Quinqueloculina
dutemplei, Q. longirostra and Q. pulchella live at depths ranging
from 23 to 42 m (Chierici et al., 1962) and 19 species, including only
2 species belonging to Quinqueloculina, Le. Q. padana and Q. seminulum,
several species of Sigmoilina and Pyrgo, and Biloculinella labiata were
gathered at 218 m (d'Onofrio, 1959).
In the Ionian Sea Triloculina abounds at 15 m, Quinqueloculina
between 12 and 30 m; the numbers of both genera decrease down to 100 m
(Iaccarino, 1969). In the Ligurian Sea the Miliolidae occur in large
numbers from 20 to 90 m, Triloculina tricarinata being particularly
numerous down to 20 m (Giunta, 1955). In the Beirut region the percentage
share of Miliolidae changes with depth. At 11 m they form 10 per cent
of the whole population, at 27 m 45 per cent, at 54 m 19 per cent and at
246 m 8 per cent, Sigmoilina, Miliolinella and Biloculinella being dominant
and Quinqueloculina showing a considerable fall in number. Biloculinella
labiata and Nummoloculina contraria also occur at the greatest depth
given above (Moncharmont Zei, 1968). In the Red Sea the Miliolidae and
Textulariidae prevail at depths ranging from 21 to 73 m and both these
families are represented from 70 to 300 m but the Textulariidae are
dominant (Said, 1950).
The Miliolidae can also live in environments of reduced salinity. For
example, Adams and Haynes (1965) list 14 species, mainly of the genera
Quinqueloculina, Triloculina and Miliolinella, from the Holocene and
contemporary marshes and estuaries in northern Wales (Great Britain).
Lowman (1949) records their occurrence in strongly brackish and nearshore
marine waters in the Gulf of Mexico (together with Elphidium and
Rotalia). Some forms tolerate low temperatures, e.g. Pyrgo, which is also
present in arctic waters and at great depths, down to 2000 m (Green, 1960)
and as deep as 2500 m in the north-eastern part of the Pacific Ocean
(Saidova, 1964).