实验十六 土壤亚系统无脊椎动物多样性的调查及测定.pdf

实验十六 土壤亚系统无脊椎动物群落的多样性 附录 主要土壤动物类群的多样性及其检索 Ⅰ．主要土壤动物类群分门、纲检索表 1．单细胞动物原生动物门 Protozoa ······················································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································································多细胞动物2 2．明显分为头、足和内脏囊 3 部分，具外套膜；足部发达、扁平，位于身体腹面；大多数种类具有 1 螺旋形贝壳软体动物门 Mollusca，腹足纲 Gastropoda 身体不具以上特征3 3．无足4 有足10 4．无头5 有头节肢动物门 Arthropoda，昆虫纲 Insecta（部分） 5．无体节6 具体节7 6．体前端扩大成半月形头瓣扁形动物门 Plathelminthes，涡虫纲 Turbellaria 体前端不扩大线虫动物门 Nematha 7．体节较多环节动物门 Annelida 8 体节较少9 8．身体前、后端各有一个吸盘；身体扁平或呈圆柱形蛭纲 Hirudinea 无吸盘；身体呈细长圆柱形寡毛纲 Oligochaeta 9．体长 1 mm 以下；头前端具轮盘，其上有 1、2 圈纤毛轮形动物门 Rotifera 体长 1 mm 以上，头不具轮盘节肢动物门，昆虫纲 Insecta（部分） 10．足 4 对，无节，爪 4 个以上缓步动物门 Tardigrada 足一般不为 4 对；若为 4 对，则足有节，爪 1~3 个节肢动物门（部分）11 11．大多数体节每体节各有两对足倍足纲 Diplopoda 1 体节最多 1 对足12 12．足 15 对或 15 对以上唇足纲 Chilopoda 足不超过 14 对13 13．足 5 对以上14 足不多于 5 对17 14．触角分叉蠋纲 Pauropoda 1触角不分叉15 ··································································································································································································································································································································································································································································································································································································································································································································································································································································································································15．无尾须；胸足细小，腹足短粗，筒状昆虫纲（部分） 具尾须；足形态多样，但腹足不呈筒状16 16．体小而细长，体长约 2~8 mm，全身乳白色，整体分为头部和躯干部；触角 1 对，长而多节（平均 30~40 节） ，呈简单的线形；步足 11~12 对 综合纲 Symphyla 体平扁或侧扁，分为头、胸、腹 3 部分；触角 2 对，第一对小，第二对大；一般具 20~21 体节（不包括尾节） ；除腹部末节外，通常每节具 1 对附肢软甲纲 Malacostraca 17．足 5 对，第一对适于捕食，第二、三、四对为游泳足，第五对很退化桡足纲 Copepoda 足 5 对以下18 18．足 4 对蛛形纲 Arachnida 足 3 对昆虫纲（部分） Ⅱ．主要土壤动物类群概述及常见类群分目检索 （一）扁形动物门 Plathelminthes 涡虫纲 Turbellaria 本纲动物大部分水栖，小部分陆栖。

中国目前发现的陆生涡虫均属三肠目（Tricladida）的笄涡虫科（Bipaliidae） （二）轮形动物门 Rotifera 轮虫大多生活于水环境中，生活于土壤中的类群主要属于双巢纲（Digononta）蛭态目（Bdelloidea） ，小部分属于单巢纲（Monogononta）游泳目（Ploimida） 土栖轮虫喜好有机质丰富的土壤，以有机碎屑、细菌等为食在有苔藓覆盖的地方最多，土壤表层多湿的落叶层中也有相当数量，在腐叶层和腐殖层也有发现我国迄今记录到土栖轮虫 2 纲 2 目 6 科 （三）线虫动物门 Nematha 线虫是土壤动物中数量最多的类群之一，为典型的湿生土壤动物，在植物根系发达的土壤上层数量最多土壤线虫体型较小，体长多为 0.5~4 mm，很少超过 1 cm体细长圆筒形，两端略尖；体壁具角质层，光滑、坚韧而富有弹性；身体不分节，或仅体表具横皱纹迄今我国已发现土壤线虫 2 纲 8 目 56 科 （四）环节动物门 Annelida 陆栖环节动物主要包括寡毛纲的多数种类和蛭纲的部分种类迄今我国已发现寡毛纲 4 目 12 科陆生和两栖蛭类主要为无吻蛭目（Arhynchobdellida）的一些种类（主要特征为没有可伸缩的吻） ，包括两个科，见于我国大部分地区。

寡毛纲分目检索表 1．体长一般小于 40mm；体节和环带常不明显；雄孔和精漏斗隔膜仅间隔半节（图 216-3）（小蚓类）2 ·····································································································································································································································································································。