Polystomella minuta Reuss, 1865

Margerel, Jean-Pierre & Poignant, Armelle, 2018, Two poorly known species of Foraminifera: Polystomella minuta Reuss, 1865 from the Oligocene of Germany (Bavaria) and P. falunica Allix, 1913 from the Miocene of western France (Touraine). Designation of a neotype for P. falunica, Geodiversitas 40 (19), pp. 497-504 : 498

Polystomella minuta Reuss, 1865

Polystomella minuta Reuss, 1865: 478 , pl. 4, fig. 6a-b.

Elphidium minutum – Cushman 1939: 40, pl. 10, fig. 22 (Reuss figure), non figs 23-25 (the figure of Cushman is the one from Reuss).

ORIGINAL DIAGNOSIS. — “Klein (0.45-0.5 Millim.), rund, wenig zusammengedrückt, mit sehr stumpfwinkeligem Rücken, ohne Nabel und Nabelscheibe. Zehn schmale, sehr wenig gebogene Kammern mit schwach vertieften linearen Nähten und sehr kleinen, wenig zahlreichen, punktförmigen Nathgrübchen. Die Septalfläche halbmondförmig, breiter als hoch, ohne sichtbare Mündungen”.

AGE. — Upper Oligocene.

TYPE LOCALITY. — No type locality is given, but three localities are pointed out: Harleshausen, Dieckolzen and Bodenburg, situated south of Hannover.

OCCURRENCE. — Very rare.

STRATIGRAPHICAL DISTRIBUTION. — Fide Reuss (1865), Upper Oligocene.

REMARKS

The figures of Le Calvez (1966, 1970) are inspired by the specimen of the collection on the Parisian Basin. Her figure published in 1966, which unfortunately is a drawing, appears to be identical to the picture published in 1970. The main difference with Reuss species is the presence of numerous pustules on the test. These pustules are not mentioned by Reuss in his description of the species.

Dr F. Rögl believes that the Le Calvez species is not the one of Reuss (message to AP 2014).

Elphidiella minuta is quoted by Reiser (1987: 93) in the Oligocene and noteworthy in the Bavarian Chattian where it would be not rare. Unfortunately, it is not figured and the author only gives the Reuss reference. As for Miocene references, they probably always concern Polystomella falunica .

Finally, many of all the illustrations since 1974 of the Oligocene “ Polystomella minuta ” correspond to other species, perhaps pro parte to, Polystomella latidorsata Reuss, 1864 .

Asides from the Ellis & Messina catalogue (1940 and supplements), only two references ( Hosius 1895; Beutler 1914) are given with the number of pages but no indication of illustrations.

In 1997, one of us (AP) evoked the problem of mixing both species.

To conclude, we think that now it’s impossible to give a description of Polystomella minuta , it would be necessary to examine samples from the Reuss localities to obtain topotypic specimens.