论文部分内容阅读
In the light of Synchrotron Radiation X-ray Tomographic Microscopy(SRXTM),the internal structure of Markuelia hunanensis is revealed.In one example,vitrification and peeling show the annuli hidden under the chorion.Sectioning and 3-D reconstruction display an intact digestive tract from the inverted introvert to the terminal anus.The inverted introvert forms a rugby cavum. The following digestive tract is rope-like coiling,parallel to the body axis,about 650 um in length, and uniform in diameter(～80μm).An exquisitely preserved pipe-like structure is hidden in the middle of the rope-like structure,diameter 20-40μm,with a length of～120μm.We interpret this pipe-like structure as the possible epidermis of the gut and its surroundings as the possible residue of musculature,similar to that in Priapulans.The two symmetrical rod-shape structures connecting the body wall and digestive tract are interpreted as the possible retractor muscles.After comparing the well preserved Left-form and Right-form Body of Markuelia,we suggest that they may represent a dimorphism.Counted directly,one sample of Markuelia hunanensis possesses 62 annulations and the other 68.
In the light of Synchrotron Radiation X-ray Tomographic Microscopy (SRXTM), the internal structure of Markuelia hunanensis is revealed. In one example, vitrification and peeling show the annuli hidden under the chorion. Sectioning and 3-D reconstruction display an intact digestive tract from the inverted introvert to the terminal anus. The following introvert forms a rugby cavum. The following digestive tract is rope-like coiling, parallel to the body axis, about 650 um in length, and uniform in diameter (~ 80 μm) preserved pipe-like structure is hidden in the middle of the rope-like structure, diameter 20-40 μm, with a length of ~120 μm. We interpret this pipe-like structure as the possible epidermis of the gut and its surroundings as the possible residue of musculature, similar to that in Priapulans. The two symmetrical rod-shape structures connecting the body wall and digestive tract are interpreted as the possible retractor muscles. After comparing the well preserved Left-form and Right-form Body of Markuelia, we suggest that they may represent a dimorphism. Counted directly, one sample of Markuelia hunanensis possesses 62 annulations and the other 68.