Abstract
This paper deals with bifurcation angle of a reptant, dichotomously branchingAulopora cf.enodis colony (Silurian, Gotland). It can be demonstrated, that during early astogenetic growth the branching angle between offsetting corallites decreases rapidly from 165° to 100° averagely during later growth stages. This growth pattern resembles development of similar dichotomous branching uniseral bryozoans, e.g. PaleozoicCorynotrypa species or MesozoicStomatopora species.
Kurzfassung
Ein vollständig überliefertesAulopora cf.enodis-Corallum aus dem Silur von Gotland wird beschrieben. Die Sprossung erfolgt am terminalen Ende der Coralliten jeweils dichotom. Der Verzweigungswinkel nimmt nach den ersten beiden Sprossungs-Generationen (165°, 135°) rasch ab und stellt sich bei ca. 100° ein. Vergleichbare Entwicklungen während der Astogenese konnten bisher vor allem an Bryozoen-Taxa mit ähnlicher Verzweigungsrate und dichotomem Knospungsrhythmus aufgezeigt werden, z.B. bei paläozoischenCorynotrypa-Arten oder mesozoischenStomatopora-Arten.
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Helm, C. Astogenese vonAulopora cf.enodis Klaamann 1966Visby-Mergel, Silur von Gotland. Paläontol Z 73, 241–246 (1999). https://doi.org/10.1007/BF02988037
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DOI: https://doi.org/10.1007/BF02988037