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Carnets Geol. 16 (3)

Lithothamnion crispatum: long-lasting species
of non-geniculate coralline algae (Rhodophyta, Hapalidiales)

Giovanni COLETTI 1
Juraj HRABOVSKÝ 2

Daniela BASSO 3

Abstract: The examination of fossil Lithothamnion specimens ranging in age from the Early Miocene to
the Pleistocene revealed the occurrence of multiporate conceptacle chambers pitted with depressions.
This is the diagnostic feature of Lithothamnion crispatum, a cosmopolitan hapalidiacean with a wide
depth range in modern oceans. The comparison of the microscopic anatomy of both the fossil and mo-
dern L. crispatum confirmed that they are conspecific. Therefore, this species has a long stratigraphic
distribution starting at least 20 My ago, without significant morphological changes in either reproductive
or vegetative anatomy.

Key Words: Morphology; multiporate conceptacle roof; Tethys; Melobesioideae; Miocene.

Citation: COLETTI G., HRABOVSKÝ J. & BASSO D. (2016).- Lithothamnion crispatum: long-lasting species of
non-geniculate coralline algae (Rhodophyta, Hapalidiales).- Carnets Geol., Madrid, vol. 16, nº 3, p. 27-
41.

Résumé : Lithothamnion crispatum : une espèce d'algue coralline non-geniculée persistante
dans le temps (Rhodophyta, Hapalidiales).- La révision d'exemplaires fossiles de Lithothamnion dont
l'âge varie du Miocène inférieur au Pleistocène a montré la présence de chambres de conceptacles multi-
porés marquées par des dépressions, ce qui constitue le caractére diagnostique de Lithothamnion
crispatum, une algue de la Famille des Hapalidiaceae, cosmopolite et vivant à une large gamme de
profondeur dans les océans actuels. La comparaison des structures microscopiques de spécimens fossiles
et modernes de L. crispatum confirme qu'ils doivent être considérés comme conspécifiques. Par consé-
quent, cette espèce a une répartition stratigraphique très grande, commençant il y a au moins 20 mil-
lions d'années, sans variation morphologique significative dans les parties reproductives ou végétatives
de son anatomie.

Mots-clefs : Morphologie ; conceptacles à toit multiporé ; Téthys ; Melobesioideae ; Miocène.

Introduction The aim of this paper is to contribute to this
development by introducing a new diagnostic
According to taxonomic uniformitarianism it character never seen nor described before in
is possible to extrapolate the ecological signifi- the fossil material: the presence of pits sur-
cance of modern species to their fossil counter- rounding the pore canals in the roof of the
parts. In most cases this core principle of paleo- sporangial conceptacles. This is the key mor-
ecology can be safely applied at least for paleo- phological feature of the non-geniculate coral-
environments not older than the Miocene (HAU- line Lithothamnion crispatum HAUCK, 1878,
NOLD et al., 1997; AGUIRRE et al., 2000). To unknown as a fossil until now. Fossils from the
accomplish this goal, recent species need relia- Pleistocene and the Miocene have been compa-
ble identification in the fossil record achievable red with modern Mediterranean specimens of
through the application of the same criteria used L. crispatum to assess and study their rela-
in biological classification. In this way, the biolo- tionship. The modern cosmopolitan distribution
gical and paleontological classifications can be of L. crispatum includes the Mediterranean
made consistent as far as fossil preservation (BRESSAN and BABBINI, 2003; BASSO et al.,
allows. For coralline algae this approach has 2011), the Atlantic Ocean (KEATS et al., 2000;
been developed in various contributions (BRAGA NÓBREGA -FARIAS et al., 2010), the Indian Ocean
et al., 1993; BASSO et al., 1996, 1997; RASSER (SILVA et al., 1996), the Pacific coast of
and PILLER, 1999, 2000; BASSI et al., 2009; IRYU Australia (HARVEY et al., 2003) and the
et al., 2009; AGUIRRE et al., 2012; WOELKERLING northern coast of New Zealand (NEILL et al.,
et al., 2014; HRABOVSKÝ et al., 2015). 2015). Living specimens have been collected

1 Corresponding author
Department of Environmental Sciences and Earth Sciences, University of Milano Bicocca, Piazza della Scienza 4, 20126
Milano (Italy)
g.coletti@campus.unimib.it
2 Department of Geological sciences, Masaryk University, Kotlářská 2, 611 37 Brno (Czech Republic)
3 Department of Environmental Sciences and Earth Sciences, University of Milano Bicocca, Piazza della Scienza 4,
20126 Milano (Italy)
daniela.basso@unimib.it
Published online in final form (pdf) on February 20, 2016
[Editor: Bruno GRANIER; language editor: Stephen CAREY]

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