Cyanobacteria-containing biofilms from a Mayan monument in Palenque, Mexico

TL;DR: The structural characterization and species composition of biofilms from the walls of one of the buildings at the archaeological site of Palenque, Mexico, are reported and the implications for the development and permanence of species capable of withstanding temporal heterogeneity in and on El Palacio are discussed.

Abstract: Surfaces of buildings at the archaeological site of Palenque, Mexico, are colonized by cyanobacteria that form biofilms, which in turn cause aesthetic and structural damage. The structural characterization and species composition of biofilms from the walls of one of these buildings, El Palacio, are reported. The distribution of photosynthetic microorganisms in the biofilms, their relationship with the colonized substratum, and the three-dimensional structure of the biofilms were studied by image analysis. The differences between local seasonal microenvironments at the Palenque site, the bioreceptivity of stone and the relationship between biofilms and their substrata are described. The implications for the development and permanence of species capable of withstanding temporal heterogeneity in and on El Palacio, mainly due to alternating wet and dry seasons, are discussed. Knowledge on how different biofilms contribute to biodegradation or bioprotection of the substratum can be used to develop maintenance ...

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SUPPLEMENTARY MATERIAL
Table 2. Species identified in sampling sites at El Palacio (Palenque).
Taxa Size Location Figure
Cyanobacteria
Chroococcales
Synechococcaceae
Aphanothecoideae
Aphanothece castagnei
(Bre
´
bisson) Rabenhorst
Cells 4.1-(5.3)76.6 mm wide and
2.6-(4.9)77.2 mm long
I
III
IV
Gloeothece cf. palea (Ku
¨
tz.)
Rabenhorst
Cells 2.3-(2.4)72.6 mm wide,
4.6-(7.9)711.2 mm with sheath and 2.6-
(4.9)77.26 long,
6.6-(9.2)711.8 mm with sheath.
I
II
III
IV
Microcystaceae
Gloeocapsa calcicola Gardner Cells 2.6-(3.3)74.2 mm wide and
9.2-(13.8)718.5 mm with sheath
I
II
III
IV
Gloeocapsa quaternata Ku
¨
tzing Cells 2.3-(2.9)73.5 mm wide and
3.2-(5.3)77.5 mm long. With sheath 5-
(5.7)76.5 mm wide and
6-(7.2)78.5 mm long
I
II
III
IV
Chroococcaceae
Asterocapsa divina Koma
´
rek Colonies 13.3-(63.9)7114.5 mm wide. Cells
6.6-(9.9)713.3 mm wide and 9.9-
(12.4)714.9 mm long. Cells with sheath
9.9-(25.7)741.5 mm wide
II
III
IV
Chroococcus cf. schizodermaticus
W. et G.S. West
Colonies de 7-(13.5)720 mm wide. Cells 4-
(8.5)713 mm wide and
5-(10.5)716 mm long
I
IV
Oscillatoriales
Pseudoanabaenaceae
Leptolyngbyoideae
Leptolyngbya cf. compacta
(Ku
¨
tzing ex Hansgirg) Koma
´
rek
et Anagnostidis
Filament diameter. Trichomes
1.3-(1.6)72 mm wide and cells
1.9-(2.6)73.3 mm long, sheath
1.5-(1.7)72 mm thick
I
IV
Schizotrichaceae
Schizothrix bosniaca (Hansgirg)
Geitler
Trichomes 2.4-(4.1)75.7 mm wide, cells 3.7-
(7.3)711 mm long
I
IV
(continued)

SUPPLEMENTARY MATERIAL
Table 2. (Continued).
Taxa Size Location Figure
Nostocales
Scytonemataceae
Scytonema guyanense (Mont.)
Bornet et Flahaut
Cells 4.9-(9.5)714.1 mm wide and
3.4714.9 mm long. Heterocysts 3.4-
(9.2)714.9 mm wide and
5.5-(10.8)716.1 mm long.
Sheath 8.3-(10.5)712.7 mm
I
IV
Nostocaceae
Nostoc commune Vaucher ex
Bornet et Flahaut
Cells 5.8-(6.6)77.4 mm wide and
4.9-(7.4)79.9 mm long. Heterocysts 6.6-
(7.4)78.3 mm wide and 7.4-(7.8)78.3 mm
long
I
IV
Chlorophyta
Trentepohliophyceae
Trentepohliales
Trentepohlia aurea (Linn) Martius Young cells: 3.9-(16.7)729.5 mm wide and
3.9-(13.6)723.2 mm long. Mature cells:
9.9-(18.2)726.5 mm wide and 18.2-
(35.2)752.1 mm long. Sporangia: 15.8-
(22.1)728. 2 mm wide and 17.8-
(25.5)733.2 mm long
III
IV