Nitellopsis (Tectochara) merianii (Al. Braun ex Unger, 1852 ), Grambast & Soulie-Marsche, 1972

Sanjuan, Josep & Martín-Closas, Carles, 2014, Taxonomy and palaeobiogeography of charophytes from the Upper Eocene- Lower Oligocene of the Eastern Ebro Basin (Catalonia, NE Spain), Geodiversitas 36 (3), pp. 385-420 : 406

Nitellopsis (Tectochara) merianii (Al. Braun ex Unger, 1852) Grambast & Soulié-Märsche, 1972

( Fig. 8 L-N)

Chara meriani Unger, 1852: 82 , pl. 25, figs 10-12.

Tectochara meriani – Grambast & Grambast-Fessard 1954: 668.

Nitellopsis (Tectochara) meriani – Grambast & Soulié- Märsche 1972: 11.

DISTRIBUTION. — Nitellopsis (Tectochara) merianii appears to be exclusive to Europe during the Upper Eocene (Upper Priabonian) and Lower Oligocene (Rupelian) ( Table 5 ). It has been reported in Rupelian lacustrine deposits from many French localities, i.e. Paris Basin ( Grambast & Paul 1965; Riveline 1986), Aquitaine ( Feist & Ringeade 1977), the western sector of Languedoc ( Grambast 1962; Feist- Castel 1971) and Provence ( Touraine 1971) basins. It was also reported in Lower Oligocene beds in the Rhine Graben in Germany ( Mädler 1955; Schwarz 1997) and in Lower Oligocene deposits from the Molassic Swiss Basin ( Kissling 1974; Reichenbacher et al. 1996). In Spain, this species has been documented in Upper Eocene-Lower Oligocene deposits from the Ebro Basin ( Choi 1989; Feist et al. 1994) and from Oligocene rocks in the central Iberian Peninsula (Loranca Basin) by Juliá de Agar (1991). Recently, Sanjuan & Martín-Closas (2012) reported the oldest record of the species in the Upper Priabonian of the eastern Ebro Basin, namely at Torre Casanova (Moià), El Talladell and Vinaixa ( Tables 2 , 4). During the Uppermost Oligocene-Lower Miocene, this species expanded from western Europe across the Paratethys realm to NE China and SE Asia, ranging from latitude 18°N to 50°N and covering the entire Eurasian landmass (Soulié-Märsche et al. 1997 and references therein; Soulié-Märsche et al. 2002; Sanjuan & Martín-Closas in press). In Eastern Europe, this species was also recorded in Lower Oligocene deposits from Slovenia ( Ettinghausen 1872) and Romania ( Iva et al. 1970; Baciu & Feist 1999). Mädler & Staesche (1979) reported this species in many localities attributed to Early Oligocene from Turkey ( Table 5 ).

DESCRIPTION

Large gyrogonites, variable in size, 818-1262 µm high (mean 1084 µm), and 716-1045 µm wide (mean 909 µm), normally ovoid but sometimes ellipsoidal in shape with an isopolarity index of 96-146 (mean 121).Spiral cells 126µm wide, generally convex.Eight to eleven (often nine) convolutions visible in lateral view. Apex nitellopsidoid, slightly convex or subrounded, with well-marked thinning and narrowing of the spiral cells in the periapical zone.Apical nodules present, more or less prominent. Base rounded or slightly conical with large basal pore, 100 µm across, and located within a pentagonal funnel.

REMARKS

Ŋis species shows a notably reduced size in comparison with coeval Nitellopsis species such as N. (T.) wannacotti , N. (T.) aemula and N. (T.) latispira , which are about 300 µm larger and are in general more rounded in shape.

Figures

FIG. 8.— Charophytes from the Artés and lateral south-western Formations,Ebro Basin:A-C, Lychnothamnus grambastii (Feist-Castel, 1971), Torre Casanova section; A, apical view, no. 80100 MGSCB, sample TC-9; B, lateral view, no. 80101 MGSCB, sample TC-9; C, basal view,no.80102 MGSCB,sample TC-9;D-F, Lychnothamnus vectensis (Groves,1926),Santpedor and Rubió sections;D, apical view, no. 80103 MGSCB, sample RB-3; E, oblicuous view, no. 80104 MGSCB, sample SP-18; F, lateral view, no. 80104 MGSCB, sample SP-18; G, basal view, no. 80105 MGSCB, sample SP-4; H-K, Lychnothamnus major (Grambast & Paul, 1965), Sarral section and El Talladell outcrop; H, apex, no. 80106 MGSCB, sample BO-1; I, lateral view, no. 80107 MGSCB, sample BO-1; J, lateral view, no. 80108 MGSCB, sample SA-19; K, basal view, no. 80109 MGSCB 09, sample SA-19; L-N, Nitellopsis (Tectochara) merianii (Al. Braun ex Unger, 1852), Vinaixa section; L, apical view, no. 80110 MGSCB, sample VI-5; M, lateral view, no. 80111 MGSCB, sample VI-5; N, basal view, no. 80112 MGSCB, sample VI-5. Scale bar: 500 µm.