Triploporella sp.

Bucur, Ioan I., Polavder, Svetlana & Radoičić, Rajka, 2014, Lower Cretaceous Calcareous Algae And Foraminifera From Trbušnica (Vardar Zone, Serbia), Acta Palaeontologica Romaniae 10 (1 - 2), pp. 1-2 : 102

Triploporella sp.

( Fig. 7 a-g)

In three of the studied sections obtained from sample RR013234 we have identified the rests of a large Triploporella species present in transversal-oblique sections ( Fig. 7 a-d); one fragment is present in a longitudinal-oblique section ( Fig. 7 b ).

The two transversal sections differ in the size of the axial cavity and in the display of the laterals. The specimen in Fig. 7 a shows a broad axial cavity, while that in Fig. 7 d shows a narrower one. Also, the laterals seem to be less inclined in the first specimen ( Fig. 7 a ) and more inclined in the second one ( Fig. 7 d ). These features point to the fact that the alga may display a claviform thallus with a narrower external diameter and axial cavity in the lower part ( Fig. 7 d ) broadening towards the upper part ( Fig. 7 a ). Secondary laterals are not visible (possibly they are primarily not-calcified). Typical for the specimens from Trbušnica are the very small cyst- containers ( Fig. 7 b, c , e-g) as compared to those in other Triploporella species (e.g. Bucur et al., 2013). At a first glance, they seem to be simple cysts; when investigated in detail, some show inner round, micritic corpuscles, and can be considered intracellular receptacles-type reproducing organs – cyst-containers that are typical for the genus Triploporella and are present in most species of this genus ( Barattolo, 1980, 1981; Barattolo et al., 2013). Such small cyst-containers were recently noticed also in other Triploporella specimens identified in Upper Aptian limestones from the Apuseni Mountains ( Romania) (Bucur et al., 2013).

Dimensions (mm): D = 5.60-6.60; d = 2.00-4.20; l = 1.40-1.50; p = 0.25-0.30; w = 45-70; diameter of cyst-containers = 0.050-0.090/0.040-0.070; cyst diameter = 0.020 -0.030.

Figures

Fig. 7 Dasycladalean algae from the limestone pebbles of Trbušnica. a-g Triploporella sp. Transverse (a) and transverseoblique (d) sections; b, section of a fragment, cutting some laterals; c, enlargement of the specimen in b showing the cyst containers (arrows); e-g, enlargement of different parts of the specimen in d; a, thin section RR4525; b, thin section RR4524; d, thin section RR4527. Scale bar = 1mm (a, d); 0.25 mm (b, c, e-g).