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早寒武世澄江动物群提供了探索早期翻吻动物辐射的一个绝佳的窗口。澄江动物群翻吻动物包括8科10属10种,其中罗惠麟等(1999)依据仅有的一块不完整的标本建立Tylotitespetiolaris,并将其归入叶足动物。2002年西北大学早期生命研究所野外工作组在尖山剖面采集到两块完整的具有吻部的标本,本文籍此对该属进行了进一步完善和补充,特别是吻部和躯干表面的特征,从而说明T.petiolaris为翻吻动物。因为与澄江动物群中其他翻吻动物形态有较大差异,据此建立瘤节虫科,新科Tylotitidaefam.nov.。描述如下: 虫体较长,呈圆管状,长可达100mm,宽2～4mm。身体基本可以分吻部和躯干部两部分。吻部与Cricocosmia特别相似,为典型的三段式构造,从下到上可依次分为 、 、 段, 段与躯干前端连接,直径同于躯干,表面有10列纵向的略为弯曲的小刺(图版I,图1a,1b;插图1)。最前端吻刺最为粗壮,向后的吻刺逐渐变小。 段位于 段之前,向前略微收缩,光滑无刺。 段位于吻部顶端,可进一步分为A、B两部分:A段直径后端大于 段,表面密布斜列排列的小刺,从后向前,小刺变大;B段光滑无饰,直径小于A段。 段可强烈自由弯曲(图版I,图1a,1d)。颈部长约5mm,表面光滑无饰,直径略小于躯干。躯干表面具56～58个环脊,52排粗刺,最前面第4～6个环脊表面无?
The Early Cambrian Chengjiang fauna provides an excellent window to explore the early kennel radiation. Chengjiang fauna turnip animals include 8 families and 10 genera and 10 species, of which Luo Hui-lin (1999) based on only a piece of incomplete specimens to establish Tylotitespetiolaris, and classified as leaf-footed animals. In 2002, the field work team of Institute of Early Life, Northwest University collected two complete specimens with snout at Jianshan section. This article further complements and supplements the genus, especially the features of the snout and the trunk surface Description T.petiolaris is a kissing animal. Because there is a big difference with the morphological changes of other animals in the Chengjiang fauna, the new section Tylotitidaefam.nov was established. Described as follows: a long worm, was a round tube, up to 100mm long, 2 ~ 4mm wide. The body can basically divided into two parts, the Ministry of the trunk and torso. The snout is very similar to Cricocosmia and is a typical three-section structure, which can be divided in turn from bottom to top. The segment is connected to the front of the torso and has the same diameter as the trunk. The surface has ten longitudinal, slightly curved spines Plate I, Figs. Ia, Ib; Fig. 1). The forefront of the most robust sting, the back of the kiss sting gradually smaller. Segment in front of the segment, a little forward contraction, smooth without sting. Section is located in the top of the kiss, can be further divided into A, B two parts: A section of the back end of the diameter is greater than the section, the surface is arranged obliquely arranged small spines, from back to front, small spines become larger; B section smooth no decoration, diameter Less than A segment. Sections can flex strongly freely (Plate I, Fig. 1a, 1d). Neck length of about 5mm, smooth surface without decoration, diameter slightly smaller than the trunk. Torso surface with 56 ~ 58 ridge, 52 rows of thick thorns, the first 4 ~ 6 ring ridge surface without?