Vhx 6000

Fossil specimens were photographed with a Keyence VHX 6000 and Leica M205AF stereomicroscope. In order to observe the structures buried within the rock matrix and to produce three-dimensional models of the preserved morphology, micro-CT imaging and three-dimensional computer rendering techniques were applied. The best outcome is from specimens YKLP 16260 and CFM 00047. Specimen YKLP 16260 was first scanned with a GE Phoenix Nanotom cone beam scanner at the Bavarian State Collection of Zoology, Bavarian Natural History Collections, München, Germany, to detect the signal/noise ratio, and then with a Zeiss Xradia 520 Versa X-ray microscope at Yunnan Key Laboratory for Palaeobiology to obtain images with higher resolutions. For the Xradia 520 Versa scanning, the energy and the resolution were set at 60 kv/5w and 15.25 µm for slab a, and at 60 kv/5w and 15.89 µm, 50 kv/4w and 8.48 µm for slab b (scanned twice), to obtain a higher resolution of the anterior part of the body. Specimen CFM 0047 was scanned with a Zeiss Xradia 520 Versa X-ray microscope with the above two parameters set at 70 kv/6w and 5.41 µm for overview scanning, and at 60 kv/5w and 11.6 µm for small-field, detailed scanning.

The specimen was prepared manually with fine needles under a Nikon SMZ800 stereomicroscope and then photographed using a Keyence VHX 6000 stereomicroscope and a Leica DFC7000 T monochrome digital camera attached to a Leica M205 FA fluorescence stereomicroscope (figure 1c). Backscattered electron (BSE) image capture and energy-dispersive x-ray spectroscopy (EDS) analysis were performed using an FEI Quanta 650 scanning electron microscope (SEM) under low vacuum and high accelerating voltage (30 kV) (figure 1f,k,i,n) and a JEOL JSM-IT500 SEM under low vacuum with a voltage of 15 kV (figure 2c,g; electronic supplementary material, figure S1). Photographs were processed in Adobe Photoshop and CorelDRAW SE 2021.