Description of a new Homidia species(Collembola: Entomobryidae) with labial chaetae expanded

Homidia triangulimacula sp. nov. is described from Tiantong National Forest Park, Zhejiang Province. It can be easily discriminated from other species of Homidia by triangular dark patch on dorsal central mesothorax, labial chaeta M replicated and labial basal and posterior labial chaetae expanded, 6＋6 macrochaetae on posterior abdominal segment IV, and middle S-chaeta posterior to macrochaeta m3 on abdominal segment V. A detailed morphological character comparison and a key to species with chaetae expanded on labium or posterior labium in Homidia are provided here.

单环刺螠(Urechis unicinctus)刚毛结构与成分分析

单环刺螠(Urechis unicinctus)具有腹刚毛和尾刚毛。为探究单环刺螠刚毛结构与成分,本文采用扫描电镜对其刚毛的内外形态进行了观察;利用傅里叶红外光谱、X-射线衍射分析了其主要成分;基于现有的转录组数据分析了与其代谢相关的基因种类和潜在通路;初步分析了刚毛结构特点与其年龄的关系。结果表明,单环刺螠一般具有2根腹刚毛,8~13根尾刚毛;腹刚毛细长,弧度较大;尾刚毛粗短,弧度平缓;随年龄增长,刚毛长度和直径均有所增加;且年龄越大,刚毛表面的结节状特征越为明显。刚毛由直径约1μm的微纤维组成,呈倾斜的层状结构纵向排列,每层平均宽度为(172±27)μm;成分分析发现其主要由α-几丁质构成,还含有蛋白质成分。通过生物信息学分析发现单环刺螠体内存在与几丁质代谢相关酶,并推测了其潜在的代谢通路;研究结果为判断单环刺螠的年龄及生长状态提供了一定的理论基础。