贵州下寒武统牛蹄塘生物群中海绵新材料

描述了贵州下寒武统牛蹄塘生物群中海绵化石1新属(Zunyispongiagen.nov.),2新种(Zunyispongiatriangulariagen.etsp.nov.,Choiafanensis.sp.nov.),通过对其形态功能的分析和讨论证实了寒武纪早期海绵动物的骨骼是由细小骨针向粗大骨针演变,骨架结构从不稳定型向稳定型发展。

NEW SPONGES FROM THE LOWER CAMBRIAN OF GUIZHOU

The early Cambrian Niutitang Biota from Guizhou abounds in sponges (Zhao et al ., 1999, 2002, 2003; Yang et al ., 2000, 2003). Since discovery of the biota in 1999, the number of sponge genera amounts to 12 (Yang et al ., 2003). As proposed by Zhao et al . (2003) that the explosion of sponges might have happened during the time of the Niutitang Formation (Zhao et al ., 2003).Here in the present paper, we describe two new sponge species in the biota, including two specimens (Yang et al ., 2003, p.290, pl.I, figs. 1-2) which had been assigned to Choia sp.As discussed by Yang et al . (2003), these two specimens are different from C. zunyiensis Yang and Zhao, 2003 (Yang et al .,2003,p.289,pl.I,figs.3-6) in outlines, however, fragmentary specimens make erection of a new taxon inconvincible. Currently a fairly well preserved specimen has been discovered. They show obvious difference from Choia zunyiensis Yang and Zhao, 2003 and require erection of a new species.Other two specimens here we described are similar to Hunanospongia Qian and Ding, 1988 collected from the Niutitang Formation at Yangjiaping, Shimen, Hunan (Ding et al .,1988, pl.4, figs. 6-8; Qian, 1989, text-figs. 49-50), and to Sanshapentella dapingi Mehl and Erdtmann,1994 at Sancha, Dayong, Hunan (Mehl et al ., 1994, p.316, pl.1, figs.1-3; text-fig.1).But our new specimens reported here are different from Hunanospongia Qian and Ding, 1988 and Sanshapentella dapingi Mehl and Erdtmann, 1994, and described as a new genus and species.