Combined Molecular and Morphological Taxonomy of the Beccarii/T3 Group of the Foraminiferal Genus Ammonia

  • publication
  • 23-10-2019

Bruce W. Hayward, Maria. Holzmann, Masashi Tsuchiya. Journal of Foraminiferal Research (2019) 49 (4): 367–389. https://doi.org/10.2113/gsjfr.49.4.367

A quest to collect live specimens of the well-known foraminifer Ammonia beccarii for sequencing has led to the recognition of five molecular species in Europe all related to it, but no live A. beccarii itself. The five molecular species all clump together in one clade (T3) of the Ammonia phylogenetic tree. All are characterized by large size, ornament on the umbilical side and a deep spiral, sutural fissure on the spiral side (beccarii morphogroup). All five molecular species can be discriminated based on distinct morphological differences as Ammonia batava (North Sea, northeast Atlantic, west Mediterranean Sea), A. corallinarum (northeast Atlantic, west Mediterranean Sea), A. pawlowskii n. sp. (Mediterranean Sea, west Indian Ocean), A. falsobeccarii (North Sea, east Atlantic seaboard, Mediterranean Sea, Persian Gulf), and A. neobeccarii (Mediterranean and Black seas). Using morphological characters, a further four species are recognized in the beccarii morphogroup for which no sequences are presently available: A. beccarii (Mediterranean Sea, northeast Atlantic), A. batava compacta (west Atlantic seaboard), A. debenayi n. sp. (west Indian Ocean), A. venecpeyreae n. sp. (west Mediterranean Sea, Gulf of Aden). One species, A. japonica (China, Japan, South Korea), for which sequences have been obtained, is included in the beccarii morphogroup based on morphological characteristics but differs genetically from the beccarii group. Another species, similar to A. falsobeccarii with secondary sutural openings on the spiral side but probably not part of the beccarii morphogroup because it lacks the spiral sutural canal typical of the group, is described as new – A. langeri (Indian Ocean, East Indies, south Australia). A growth series of A. beccarii topotypes from Rimini, north Adriatic Sea, is illustrated to aid in its recognition and a neotype designated and illustrated. Extinct fossil members of the beccarii morphogroup include A. ikebei, A. inflata, A. italica, A. nakazatoensis, A. punctatogranosa, A. reyi, A. togopiliensis, A. viennensis, and A. voorthuyseni.

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