为研究解放眉足蟹形态学特征(包括雌雄外部形态差异),补充国内解放眉足蟹相关资料的空缺,通过对采集到的野生活体进行解剖及显微观察,对成体口前板、组成口器的各个部分、第四步足、肛门及雌雄差异等进行了研究。口前板位于头胸部腹面第一、二触角的后方,口器的前方。口器由大、小颚及3对颚足共同组成,大颚单枝型,大颚须3节;第一小颚单枝型;第二小颚双枝型,内肢即小颚须棒状,外肢很发达,形成颚舟叶;第一颚足双枝型,内肢1节,外肢2节,具有上肢;第二颚足双枝型,内肢5节,外肢3节;第三颚足双枝型,内肢5节,外肢3节。胸足4对,均为单枝型,第1对为螯足,后3对为步足。腹部共7节(包括尾节),尾节无附肢,腹面有一肛门。腹部共6对腹肢,第6腹节的1对附肢与尾节共同形成尾扇,司游泳功能,是解放眉足蟹唯一的游泳器官。雌雄差异明显,生殖孔1对,雌体位于第二步足基节腹面,雄体则位于第四步足基节上;第2–5对腹肢,雌性双枝型,雄性单枝型。与虾蟹比较,其没有腹甲,头胸部腹面更近似于虾类,但背部形态又更接近蟹类。其腹部没有蟹类的腹甲沟及用于锁住腹部的搭扣,故腹部常常处于半伸展状态。第四步足则位于腹部第一腹节上,与虾蟹类明显不同。另外,观察发现其腮部及身体外表各部位均附着有双壳类软体动物。
Blepharipoda liberate Shen can clean intertidal sand, which has important ecological significances. In order to study the external characteristics and provide more information for the research and utilization of Anomura, B. liberate Shen were utilized for the dissection and observation under microscope. B. liberate Shen is unisexual; the pleopods and the location of genital pore are different between females and males. Female B. liberate Shen has four pairs of endopodites that are located in the abdomen; however, male B. liberate Shen has no endopodites. The location of genital pores of female B. liberate Shen are on the venter of the basis pereopod II, while the genital pores of male B. liberate Shen are located on the venter of the basis pereopod Ⅳ. The commensal bivalves are attached to body surface and gills. Similar to brachyura, B. liberate Shen have carapaces, but they have no sternum. The abdomen can not attach to the cephalothorax venter because of the lack of the stemal groove. Pleopod Ⅵ is much developed to form tail fan with telson that functions swimming like shrimps. A pair of the pereopod Ⅳof B. liberate is located in the abdomen that is different from shrimps or crabs.