Lychnothamnus grambastii (Feist-Castel, 1971) Soulié-Märsche, 1989

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 : 402-404

Lychnothamnus grambastii (Feist-Castel, 1971) Soulié-Märsche, 1989

( Fig. 8 A-C)

Stephanochara grambastii Feist-Castel, 1971: 166-168 , pl. 11, figs. 1-5.

Lychnothamnus grambastii – Soulié-Märsche 1989: 160.

DISTRIBUTION. — Lychnothamnus grambastii was previously reported from its type locality in the Lower to Middle Priabonian of the Alés Basin, southern France (Feist-Castel 1971). In the Ebro Basin, this species has been reported in many samples from the Torre Casanova (Moià) locality ( Table 2 ). Ŋe new data not only widen its distribution to the south but also its biostratigraphic range, reaching now the Upper Priabonian, since it occurs in association with Harrisichara tuberculata .

DESCRIPTION

Medium to large gyrogonite, variable in size, 667- 1000 µm high (mean 850 µm), and 560-859 µm in width (mean 703 µm), normally inversed pearshaped to ellipsoidal with an isopolarity index of 100-144 (mean 120). Spiral cells 100 µm wide, convex and smooth. Eight to ten (frequently nine), convolutions are visible laterally. Apex flat or slightly convex. Spiral cells display marked thinning resulting in a periapical depression. Apex ornamented by tubercles, frequently comma shaped and about 80 M m high and 100 M m wide. Base slightly conical with large basal pore, about 80 µm across, and located within a well-marked funnel.

REMARKS

Lychnothamnusgrambastii showssimilardimensionsand morphology to Lychnothamnus edwardsii ( Grambast, 1958) Soulié-Märsche, 1989 with both species having apical nodules and a basal funnel. However, whereas Lychnothamnus grambastii shows a slightly pointed base which finishes in a well-marked and wide funnel, Lychnothamnus edwardsii shows a rounded base with a superficial basal funnel. Also, Lychnothamnus grambastii does not show a periapical constriction which occurs in Lychnothamnus edwardsii .

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.