Oogenesis, fertilization, and first cleavage of Dicyema aegira McConnaughey and Kritzler, 1952 (Mesozoa: Dicyemidae).

  title={Oogenesis, fertilization, and first cleavage of Dicyema aegira McConnaughey and Kritzler, 1952 (Mesozoa: Dicyemidae).},
  author={Robert B. Short and Raymond T. Damian},
  journal={The Journal of parasitology},
  volume={53 1},

Dicyemid’s dilemma: structure versus genes. The unorthodox structure of dicyemid reproduction

Immunelectron microscopy confirms the somatic condition of mature sperm, revealing somatic histone H1 immunoreactivity over the nucleus, which can be interpreted as synapomorphy shared with Protozoa, Porifera and Cnidaria.

Developmental patterns of the hermaphroditic gonad in dicyemid mesozoans (Phylum Dicyemida)

The development of the hermaphroditic gonad, the infusorigen, was studied in fixed specimens of 16 species belonging to four genera of dicyemid mesozoans and found that mature infusorigens are similarly organized in all species examined.

Dicyema Pax6 and Zic: tool-kit genes in a highly simplified bilaterian

The presence and expression of the two tool-kit genes in Dicyemid suggests that they can be very versatile genes even required for the highly reduced bilaterian like Dicyema, and may be useful models of evolutionary body plan simplification.

Development of the Infusoriform Embryo of Dicyema japonicum (Mesozoa: Dicyemidae).

The cleavage pattern and cell lineage of the infusoriform embryo of the dicyemid mesozoan Dicyema japonicum were studied in fixed material with the aid of a light microscope and the cell lineage appears to be invariant among embryos, apart from the derivation of the lateral cells.

The dicyemid Mesozoa as an integrated system for morphogenetic studies. I. Description, isolation and maintenance.

An axenic, nearly defined, medium in which the misozoans can be kept for over three months has been developed and methods for isolating and maintaining the organisms are described.



Gametogenesis and fertilization in the Mesozoan Dicyema aegira

Observations indicated that spermatozoa emerged from the axial cell soon after their formation and made contact with oocytes early, often before these were fully grown, and precluded precocious sperm entry and the penetration of more than one spermatozoon.

The Life-History and Systematic Relations of the Mesozoa

Although Hyman noted that most zoologists regard the Mesozoa as degenerate flatworms, she designated the group as a phylum, lower than the sponges in taxonomic status.