Comparing cnidocyst sizes among populations of Bunodosoma (Cnidaria: Actiniaria: Actiniidae) from the South Atlantic west Coast

BENETI, J.; GARESE, A.; ACUÑA, F. H.; MORANDINI, A. C.

ZOOLOGISCHER ANZEIGER

ELSEVIER GMBH

Año: 2019 p. 126 - 137

0044-5231

The simplicity of a sea anemone polyp hinders the differences between species andpopulations, as very few external and internal morphological characters vary enough todistinguish closely related groups. Variations in size of different cnidocyst types could be animportant way to characterize populations of sea anemones. We aim to identify whichcnidocyst types could be useful to distinguish the variation between sea anemone populations,tested for two species of genus Bunodosoma from the South Atlantic west coast: Bunodosomacaissarum from the Brazilian coast, and B. cangicum from the Brazilian and Uruguayancoasts.We measured cnidocysts several parts of the sea anemones: acrorhagi, external andinternal tentacles, column, actinopharynx and filaments, comprising a total of 35,593measured capsules. Comparissons between cnidocysts lengths from each tissue type wereperformed by Generalized Linear Models. In B. caissarum, basitrichs from external andinternal tentacles were found to be useful for detecting differences between populations andmay indicate a latitudinal gradient. For B. cangicum, these aspects should be further analyzedin basitrichs from external tentacles, holotrichs from acrorhagi and microbasic bmastigophoresfrom the filaments. The basitrich from tentacles were found to be the mostinformative cnidae type in both species for population studies in a latitudinal sense.