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The Lithothamnion Limestone constitutes the uppermost carbonate unit of the Bolognano Formation outcropping in the Majella structure (Central Apennines, Italy). It represents the northern extension of the large Apulia Carbonate Platform and preserves an excellent record of the progressive decay of trophic conditions due to the approach of foredeep systems characterized by turbiditic siliciclastic sedimentation during the early Messinian. Sedimentological and compositional analyses were used to reconstruct the depositional model and evolution of platform environmental conditions. The profile is consistent with a homoclinal carbonate ramp, with a wide middle-ramp environment in which coralline algae, mainly forming the maërl facies, dominated carbonate production. This facies was associated with seagrass meadows colonizing the inner ramp. The outer ramp was characterized by bioturbated hemipelagic marl with planktonic foraminifera and pectinids in the aphotic zone. Three main stages of ramp evolution have been identified. During the first stage, the ramp was subjected to high-energy wave-dominated conditions, which favored the development of deep rip channels in which accumulations of vertebrate bones have been identified. In the second stage, maërl facies and seagrass meadows developed, initially in an oligotrophic setting, later followed by a slight reduction in light penetration. The third stage involved a general increase in fine terrigenous sediments, together with a further decrease in light and also by the spread of coralline algal bindstone facies. This elevated terrigenous input was associated with increased trophic conditions, as also shown by the occurrence of abundant plankton and low-oxygenated foraminiferal assemblages.

The Shella Formation exposed in the southern part of Jaintia Hills comprises an alternate sequence of sand-stone and limestone members. The limestones are fossiliferous with preponderance of benthic foraminifera, e.g. Nummulitids, Alveolinids, Discocyclina, etc. The foraminiferal assemblage suggests a Early Paleocene to Middle Eocene age for the Shella Formation. A rich assemblage of fossil calcareous algae (both non-geniculate and geniculate coralline red algae and halimedacean, udoteacean and dasycldalean green algae) has been recovered from the limestone. The non-geniculate corallines are represented by genera Lithothamnion, Lithophyllum, Distichoplax, Sporolithon, Lithoporella and Spongites and geniculate corallines are represented by the genera Corallina and Jania. A few green algae, viz. Ovulites (family Udoteaceae), Halimeda (family Halimedaceae) and Actinoporella (family Acetabulariaceae (Dasycladales)) have been recovered from the study area. The overall algal assemblage indicates a shallow marine environment of normal salinity.

Coralline algae are reported here for the first time from the Kakana Formation (Middle Pliocene) of the Car Nicobar Island. The algal assemblage is represented by 10 species of crustose and articulated coralline red algae belonging to 7 genera, viz. Lithothamnion, Mesophyllum, Lithophyllum, Porolithon, Amphiroa, Corallina and Arthrocardia. Biostratigraphical, palaeoenvironmental and palaeobathymetrical implications of this assemblage are also highlighted.