Patruliuspora, F.Barattolo & V.Ionesi & P.Tibuleac, 2019

Barattolo, Filippo, Ionesi, Viorel & Ţibuleac, Paul, 2019, A new polyphysacean alga from the Miocene of Romania and its biomineralization, Acta Palaeontologica Polonica 64 (1), pp. 85-100 : 94-95

Genus Patruliuspora nov.

Etymology: In honour of Dan Patrulius (1921–1982), pioneer of dasycladalean studies in Romania.

Type species: Chalmasia morelleti Pokorný, 1948 ; middle Miocene , Podivin, Czech Republic .

Species included: Halicoryne carpatica Mišík, 1987 , Upper Triassic Carnian–Rhaetian) of the Western Carpathians; Acicularia valeti Segonzac, 1970 ( Segonzac 1970, 1976) from the Paleocene of the French Pyrenees. It is possible that other species referred to the genus Acicularia but displaying Type D biomineralization ( Fig. 11 ) could belong to Patruliuspora .

Diagnosis. — Group of mineralized gametangia (cysts), immersed or not in a calcified mass to form ellipsoidal, irregular to variously elongated club shaped aggregates of cysts.

Remarks.— Patruliuspora is restricted to fossil taxa falling in types C and D of Fig. 11 . As discussed above, they may be the fossil remains of polyphysacean gametophores, presently belonging to Chalmasia , Halicoryne , or Acetabularia . In any case, we cannot exclude the possibility that in the past Parvocaulis or other extinct genera of Polyphysaceae , if not Triploporellaceae , might have produced equivalent mineralized aggregates of cysts.

Numerous genera are known to be mineralized parts of reproductive organs of dasycladaleans. Some of these are thought to be by-products of extracellular biomineralization of single gametophores (ampullae), Dameryella Bignot and Génot, 1998 ( Génot 2009), or tufts of gametophores Carpenterella Morellet and Morellet, 1922 ( Génot 2009). Small bodies formed by intracellular biomineralization include Acicularia Archiac, 1843 , Terquemella Morellet and Morellet, 1922 , Frederica Barta-Calmus, 1966 and Russoella Barattolo, 1983 . From a morphological point of view, Terquemella and Russoella are discoidal and not ellipsoidal, and Acicularia and Frederica are elongate club-shaped and ovoidal, respectively ( Génot 2009). However, all those genera show biomineralization of type B ( Fig. 11 ), rather than type C or D as in Patruliuspora .

Stratigraphic and geographic range.— Species of Patruliuspora ranges from Late Triassic to Miocene and includes at least three species: Patruliuspora morelleti ( Pokorný, 1948) comb. nov., P. carpatica ( Mišík, 1987) comb. nov., and P. valeti ( Segonzac, 1970) comb. nov.

The Jurassic–Cretaceous gap can be interpreted in different ways, for example: (i) because the taxon is a form-genus, it may assemble fossils from different contexts, but with similar morphologies (e.g., cladosporous, choristosporous, or goniosporous type of reproduction); (ii) the ellipsoidal aggregates may display different type of mineralization (e.g., type B and C of Fig. 11 ). Viewed in this light, Upper Jurassic–Lower Cretaceous ellipsoidal aggregates such as Acicularia elongata Carozzi, 1955 , and Acicularia endoi Praturlon, 1964 could be accommodated within the genus Patruliuspora .

Figures

Fig. 11. Scheme of intracellular mineralization in polyphysaceans (gametophores are sketched in cross section). A. Gametangia and intergametangial space not mineralized. B. Gametangia unmineralized, intergametangial space mineralized. C. Gametangia mineralized, intergametangial space not mineralized. D. Gametangia and intergametangial space mineralized.