Vertebrates in the Ludlovian Hemse Beds of Gotland, Sweden
Fredholm, Doris
Журнал:
Geologiska Föreningen i Stockholm Förhandlingar
Дата:
1988
Аннотация:
AbstractMore than 240 samples from 117 localities of the Hemse Beds were studied for vertebrates. Scales from 12 vertebrate taxa are identified and figured. The faunas include vertebrates from five major groups: (1) Acanthodians, Gomphonchus sandelensis and Nostolepis striata; (2) actinopterygians?, Andreolepis hedei; (3) cyathaspids, Archegonaspis lindstroemi; (4) thelodonts, “Logania” cuneata?, “L.” martinssoni, Phlebolepis elegans, P. ornata, Thelodus carinatus, T. parvidens, and Thelodontida gen. et sp. indet. A; (5) of osteostracans fragments were found in two samples only, belonging to a tremataspidid and an anaspid species. In the Polygnathoides siluricus conodont Zone several species show evident environmental preferences. In that conodont zone A. lindstroemi as well as the thelodonts seem to have thrived in the quiet-water of the “inner marly areas”, while G. sandelensis is significantly more abundant in limestone facies indicating an environment with higher water energy. In deeper-water facies only a few, probably long-transported, fish fragments have been found.
7.242Мб