brachiopoda est désormais compatible avec l'extension FastNews.kiwi disponible pour votre navigateur. Avec cette extension, vérifiez s'il y a des nouveaux sujets sur ce forum en un clic depuis n'importe quelle page !Cliquez ici pour en savoir plus.
Posté le: Jeu 1 Aoû - 06:11 (2013) Sujet du message: [Famille des CRANIOPSIDAE] Heliomedusa orienta
After Diandongia pista RONG 1974 Family BOTSFORDIIDAE and Lingulella chengjiangensis J. Yugan & other 1993 Family OBOLIDAE I present now with Heliomedusa orienta SUN & HOU 1987 Family CRANIOPSIDAEthe third inarticulate brachiopod from the famous Lower Cambrian Chengjiang soft-tissue fossils from China! Chengjiang in southern China is sort of a window into the time of the Middle of Lower Cambrian .
Here is an explanation of how it has come to the strange name:
Intro: Heliomedusa orienta was first identified as a jellyfish, was later described as a craniopsoid brachiopod. A number of sample of this brachiopod, measuring 3.1 - 22.0 mm long, from two new sites of the Lower Cambrian Yuanshan Formation was examined. The sample includes several with exceptional preservation of nonmineralized skeletons that reveal previously unknown features and fill a gap in our knowledge of the detailed anatomy of fossil discinids It is here reinterpreted as a discinid brachiopod on the basis of its many distinctive, discinid anatomical features, such as a longitudinally oval pedicle foramen in the anterior region such as a longitudinally oval pedicle foramen in the anterior region of the posterior sector of the ventral valve; inferred, short, but large pedicle descending ventrally from the ventral valve; inferred, paired rectus muscles in the large pedicle canal; elongate scars of paired anterior adductors; and a median septum connected to a U-shaped ridge on the ventral interior.
Here are the taxonomy, locality data and pitures:
Heliomedusa orienta SUN & HOU 1987 type species of Genus ?Heliomedusa SUN & HOU 1987, Family CRANIOPSIDAE Williams 1963, Superfamily CRANIOPSOIDEA Williams 1963, Order CRANIOPSIDA Gorjansky & Popov 1985 from Middle of Lower Cambrian, Heilinpu Formation , Yu'anshan Member, Maotianshan Chengjiang Shales, found eastern Yunnan province of southern China in Maotianshan near the town Chengjian :
Heliomedusa orienta SUN & HOU 1987 type species ?Heliomedusa SUN & HOU 1987 Family CRANIOPSIDAE Williams 1963 Superfamily CRANIOPSOIDEA Williams 1963 Order CRANIOPSIDA Gorjansky & Popov 1985 Middle of Lower Cambrian ( 525 Mio year ) Heilinpu Formation Yu'anshan Member Maotianshan Chengjiang Shales found eastern Yunnan province of southern China in Maotianshan near the town Chengjian
Detlef _________________ Detlef the friend of worldwide brachiopods