Mancini Donato, Garonna Antonio P, Pedata Paolo A
Dipartimento di Agraria, Sezione di Biologia e Protezione dei Sistemi Agrari e Forestali, Università degli Studi di Napoli "Federico II", Via Università 100, 80055 Portici (NA), Italy.
Istituto per la Protezione Sostenibile delle Piante CNR, Via Università 133, 80055 Portici (NA), Italy.
Arthropod Struct Dev. 2016 Jan;45(1):57-63. doi: 10.1016/j.asd.2015.10.003. Epub 2015 Oct 31.
Encarsia pergandiella (Hymenoptera: Aphelinidae) is an endoparasitoid with an unusual embryonic development compared to most of congeneric species and all other members of the superfamily Chalcidoidea. The developmental background of this wasp is based on an alecithal hydropic egg, with the embryo developing inside an extra-embryonic membrane which dissociates at hatching into special larva-assisting cells, the teratocytes. In E. pergandiella many teratocytes at hatching were multinucleated syncytial cells with no evidence of a cellular membrane separating the nuclei. These teratocytes during larval development produced smaller uninucleated teratocytes, through successive divisions obtained by progressive ingrowth of the plasmatic membrane, accompanied by appearance of degeneration symptoms, such as protrusions and blebs. As a consequence of this divisional process teratocytes showed a size reduction and an increase in number of about four times during the second day of larval development. Only on the third day of larval life teratocytes started to decrease in number, until total disappearance at larval maturation. This behaviour is in striking contrast with all other studied systems in which teratocytes do not divide and progressively decrease in number as the parasitoid larva develops.
佩氏恩蚜小蜂（膜翅目：蚜小蜂科）是一种内寄生蜂，与大多数同属物种以及小蜂总科的所有其他成员相比，其胚胎发育异常。这种黄蜂的发育背景基于一个无卵黄的水肿卵，胚胎在一个胚外膜内发育，该膜在孵化时解离成特殊的辅助幼虫细胞，即畸形细胞。在佩氏恩蚜小蜂中，许多孵化时的畸形细胞是多核的合胞体细胞，没有证据表明细胞核之间存在细胞膜分隔。这些畸形细胞在幼虫发育过程中产生较小的单核畸形细胞，通过质膜逐渐向内生长进行连续分裂，同时伴有退化症状的出现，如突起和泡状结构。由于这种分裂过程，畸形细胞在幼虫发育的第二天显示出大小减小，数量增加约四倍。只有在幼虫生活的第三天，畸形细胞数量开始减少，直到幼虫成熟时完全消失。这种行为与所有其他研究系统形成鲜明对比，在其他系统中，随着寄生蜂幼虫的发育，畸形细胞不分裂且数量逐渐减少。
