Format

Send to

Choose Destination
See comment in PubMed Commons below
J Morphol. 2014 Mar;275(3):295-312. doi: 10.1002/jmor.20215. Epub 2013 Oct 18.

Embryonic development of Zoraptera with special reference to external morphology, and its phylogenetic implications (Insecta).

Author information

1
Sugadaira Montane Research Center, University of Tsukuba, Sugadaira Kogen, Ueda, Nagano, 386-2204, Japan.

Abstract

The embryonic development of Zorotypus caudelli Karny (Zoraptera) is described with the main focus on its external features. A small heart-shaped embryo is formed on the dorsal side of the egg by the fusion of paired blastoderm regions with higher cellular density. The orientation of its anteroposterior axis is opposed to that of the egg. This unusual condition shows the potential autapomorphy of Zoraptera. The embryo extends along the egg surface and after reaching its full length, it migrates into the yolk. After developing there for a period of time, it reappears on the surface, accompanied by a reversion of its anteroposterior axis, finally taking its position on the ventral side of the egg. The definitive dorsal closure completes, and the prelarva hatches after perforating the chorion with very long egg tooth formed on the embryonic cuticle. Embryological data suggest the placement of Zoraptera among the "lower neopteran" or polyneopteran lineage: features supporting this are embryo formation by the fusion of paired regions with higher cellular density and blastokinesis accompanied by full elongation of the embryo on the egg surface. The extraordinarily long egg tooth has potential synapomorphy with Embioptera or Eukinolabia (= Embioptera + Phasmatodea). Together with the results from our previous studies on the egg structure, male reproductive system and spermatozoa, the close affinity of Zoraptera with Eukinolabia appears likely, that is, a clade Zoraptera + (Embioptera + Phasmatodea).

KEYWORDS:

Eukinolabia; Polyneoptera; Zorotypidae; blastokinesis; comparative embryology; egg tooth

PMID:
24136564
DOI:
10.1002/jmor.20215
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Loading ...
    Support Center