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dance to QUARANTA et al. (2007) and VANNUCCI et Carnets Geol. 16 (3)
al. (2008). Very large conceptacle chambers,
clearly resulting from the merging of two near- Results
by conceptacles, were not considered in sta-
tistical analyses. The diameter of the roof pits SYSTEMATIC PALEONTOLOGY
was measured either in the axial section of con-
ceptacles or in the equatorial section tangential Class Florideophyceae
to the roof-top layer of cells. The length of the CRONQUIST, 1960
degenerate cells (i.e., the depth of the roof pit
around the pore canal) was measured in the Subclass Corallinophycidae
axial section of the conceptacles. LE GALL & SAUNDERS, 2007
Analysis of variance (ANOVA) was employed Order Hapalidiales NELSON et al., 2015
to support the morphological comparison of the
specimens and LEVENE's test was used to assess Family Hapalidiaceae (GRAY, 1864)
the equality of variances. Since ANOVA can HARVEY et al., 2003
analyze only one character at time, the H/D
ratio of asexual conceptacle chambers was Subfamily Melobesioideae
used, because it summarizes both conceptacle BIZZOZERO, 1885
dimensions. In order to analyze differences and
similarities between the samples further, multi- Genus Lithothamnion HEYDRICH, 1897
variate statistics were performed with PRIMER 6
(KRUSKAL, 1977; FIELD et al., 1982; CLARKE and Lithothamnion crispatum HAUCK, 1878
GORLEY, 2006). BRAY-CURTIS (B-C) samples simil-
arity was calculated on average standardized For the complete list of heterotypic syno-
values of the ventral core (hypothallium) and nyms refer to BASSO et al. (2011).
peripheral zone (perithallium) cell size, concep-
tacles diameter (D) and height (H), H/D ratio Habit and vegetative structure
and roof thickness. The size of roof pits was not
included in this analysis because of the small Fruticose to foliose growth form (Fig. 1).
number of observations in the fossil and becau- Protuberances from cylindrical to lamellate, up
se no reference values was available for the to 6 mm long and 3 mm wide and commonly
modern specimens. Results, based on B-C simi- club-shaped. Thalli with monomerous organi-
larity, were plotted as hierarchical agglomera- zation, with crustose portions 100 to 500 μm
tive dendrograms. thick (Fig. 2.A-B). Ventral core up to 100 μm
thick composed of plumose filaments that arch
toward the thallus surface to form the peri-
pheral zone (Fig. 2.C). Ventral core cells are
rectangular, 9 to 28 μm in length and 6 to 12
μm in diameter (Table 2). Peripheral zone with
alternation of larger cells and smaller cells (Fig.
Figure 1: Growth-forms of fossil specimens. (A) Branches, Upper Langhian, Slovakia, Stupava-Vrchná Hora. (B)
Wavy crusts, upper part of Lower Langhian, Czech Republic, Židlochovice. (C) Crusts in a rhodolith, Burdigalian, NW
Italy, Tertiary Piedmont Basin, Villa San Bartolomeo. (D) Branch formed by stacked crusts, Pleistocene, S Italy,
Castelluccio. (E) Branch formed by stacked crusts, upper part of Lower Langhian, Romania, Lopadea Veche. (F)
Epilithic crust, Pleistocene, S. Italy, Castelluccio.
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