MILIOLIDAE - Acta Palaeontologica Polonica

54 EWA LUCZKOWSKA
Distribution. - Poland: Tortonian (Benczyn, Karsy, L~ki Dolne, Wieliczka).
Austria: Tortonian, the vicinity of Baden, Vienna Basin. France:
Redonien (Pliocene), the northwestern region of France. GFR: Lower
Miocene, Westfalia. Hungary: Tortonian, Mecsek Mts. USSR: Tchokrak
(Middle Miocene), Kuban, West Ukraine.
Quinqueloculina lentica sp.n.
(PI. VI, Figs la-c, 2a, b, 3a, b; Text-fig. 18)
Holotypus: PI. VI, Fig. 2a, b.
Paratypi: PI. VI, Figs la-c, 3a, b.
Locus typicus: Korytnica near J~drzej6w.
Stratum typicum: Lower Tortonian (Badenian), gray clay marls.
Derivatio nominis: lentica - from lenticular shape of the test.
Diagnosis: Test circular, lenticular, with inflate chambers and acute
periphery; most specimens are triloculine in appearance and have a small,
oval middle chamber with a prominent edge.
Material. - About 150 QS and 20 MS, (ColI. No. F-108, Sec. No. 85-89,
102,242-245, 247,249).
Dimensions: Holotype MS length 1.8 mm, breadth 1.8 mm, thickness
0.8 mm; Paratypes QS length 0.6-2.0 mm, breadth 0.5-1.7 mm, thickness
0.35-0.9 mm; MS length 2.3-2.6 mm, breadth 1.8-2.3 mm, thickness
0.70-0.85 mm.
Description. - Quinqueloculine stage robust, compact, of nearly circular
shape, lenticular in cross-section, periphery subacute; chambers broad,
arcuate and inflated, middle chamber small, irregularly oval, tapering at
both ends, slightly convex and with a distinct edge, fifth chamber narrow
and small, often invisible so that some specimens have a triloculine appearance;
massiline stage more flattened: sutures slightly depressed, distinct;
wall thick; surface smooth, polished; aperture large, oval, surrounded
with thickened rim, and oblique to the periphery.
Variability. A distinctive character of the species is its circular shape,
lenticular outline in cross-section, and compact structure. The chamber
edges may be more rounded in massiline forms.
Dimorphism. The massiline and large quinqueloculine forms are
microspheric (Text-fig. 18/1,2), the forms of triloculine appearance belong
to the microspheric and megalospheric II generations (Text-fig. 18/3-7);
no megalospheric I specimens have been found. Proloculus diameter:
microspheric generation 10-20 fl, megalospheric II generation 150-270 fl.
The massiline forms are rare.
Remarks. - This species is very close to Quinqueloculina pseudobuchiana
n.sp, but differs in having a more circular shape of test, and
more inflated chambers and in the triloculine appearance of most
specimens. It differs from Q. lenticularis Reuss in its more inflated
chambers and more acute periphery.