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Carnets Geol. 16 (3)

from 2 to 80 m of water depth, as rhodoliths or Material and methods
crusts attached on hard substrates, particularly
in well lit waters (KEATS et al., 2000; NÓBREGA- The specimens analyzed come from diffe-
FARIAS et al., 2010; BASSO et al., 2011; PASCELLI rent localities, with some being studied in
et al., 2013; NEILL et al., 2015). previous investigations (Table 1). Different
specimens from the same sample or from the
This species has a complex taxonomic history same outcrop were grouped together for ana-
(details in BASSO et al., 2011). In 2000 KEATS et lysis. Morphological data on Recent L. crispa-
al. established that Lithothamnion superpositum tum come from samples collected in the Egads
is conspecific with Lithothamnion indicum. Sub- Archipelago of the Western Mediterranean
sequently NÓBREGA-FARIAS et al. (2010) merged (Marettimo Island, BASSO et al., 2011).
L. superpositum with Lithothamnion heteromor-
phum. Finally, in 2011, BASSO et al. synony- Fossil samples were cut with an abrasive
mized L. heteromorphum with L. crispatum, the rock saw, and the porosity was then filled with
Mediterranean species with nomenclatural prio- epoxy resin. The surfaces were polished with
rity. As a consequence of these taxonomic revi- silicon carbide and glued onto standard glass
sions, the geographic and ecological distribution slides. The excess material was subsequently
of the species has become very broad, encom- cut off and the thickness of the sample was
passing all the oceans and both hemispheres. reduced to less than 30 μm. The thin sections
The key feature that allowed synonymizing these of coralline algal samples were then observed
species is the occurrence of pits over the roof of under light microscope to study and measure
the multiporate conceptacles, a unique feature their anatomical features. Growth-forms termi-
among Hapalidiales and a diagnostic feature in nology follows WOELKERLING et al. (1993). Vege-
the delimitation of this Lithothamnion species tative anatomy was measured along longitu-
(WILKS and WOELKERLING, 1995). These roof pits dinal radial sections (QUARANTA et al., 2007;
are the consequence of the disintegration of the VANNUCCI et al., 2008). The diameter of the
outermost cells in filaments surrounding the cells was measured including the cell wall; cell
pore canals. In the resulting structure the pore length was measured as the distance between
canal is slightly raised in the center of a rosette two primary pit connections including the cell
of degenerate cells. wall (BASSO et al., 1996). Conceptacles were
measured along their axial section, i.e., the
longitudinal section that cuts a conceptacle
medially so that the pore canal is completely
visible (AFONSO-CARILLO et al., 1984), in accor-

Table 1: Fossil samples analyzed.

Geographic Position Age N° of thin Collector Useful references
sections VANNUCCI et al., 1996, and COLETTI et al., 2015,
for further details regarding the outcrop, the geological
NW Italy-Tertiary Burdigalian 1 VANNUCCI
Piedmont Basin-Villa G. setting and coralline algae flora

San Bartolomeo REYNAUD and JAMES, 2012,
for further details on the geological setting of the basin
NW Italy-Tertiary Burdigalian 3 GC
Piedmont Basin-Uviglie FILIPESCU and GÎRBACEA, 1997; KOVÁČ et al., 2005;
SAINT-MARTIN et al., 2007; DOLAKOVA et al., 2008;
NW Italy-Tertiary 2 VANNUCCI
Piedmont Basin-Torre Burdigalian G. HRABOVSKÝ et al., 2015,
for information regarding the geological setting and
Veglio
coralline algae flora
S France-Sommières Burdigalian 1 GC
Basin-Souvignragues

Czech Republic-Central upper part

Parathethys- of Lower 1 JH

Židlochovice Langhian

Romania-Central upper part 1 JH
Parathethys-Lopadea of Lower 1 JH
Langhian 1 JH
Veche 2 DB

Slovakia-Parathethys- Upper
Stupava-Vrchná Hora Langhian

Slovakia-Parathethys- Lower

Sandberg Serravallian

S Italy-Sicily- Pleistocene
Castelluccio

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