ONH

Shield-backed Katydid identification

Steiroxys sp.

  • asgpvent
  • 3039
  • 3039cu
  • asgpside
  • 4299
  • 4681
  • subgplatefig
  • asgpvent
    1 - Steiroxys sp. adult subgenital plate ventral view, photographed in the lab.

    Specimen collected 08 20 09 Obstruction Point Area, Olympic National Park, Washington

  • 3039
    2 - Steiroxys sp. adult subgenital plate ventral view, living specimen photographed in the field.

    09/21/2009 Obstruction Point Road, Olympic National Park, Washington

  • 3039cu
    3 - Steiroxys sp. closeup of adult subgenital plate ventral view, living specimen photographed in the field.

    09/21/2009 Obstruction Point Road, Olympic National Park, Washington

  • asgpside
    4 - Steiroxys sp. adult subgenital plate side view, photographed in the lab.

    Specimen collected 08 20 09 Obstruction Point Area, Olympic National Park, Washington

  • 4299
    5 - Steiroxys sp. nymph subgenital plate ventral view, photographed in the lab.

    Specimen collected 08 15 09 Obstruction Point Area, Olympic National Park, Washington

  • 4681
    6 - Steiroxys sp. adult subgenital plate ventral view measured, photographed in the lab.

    Specimen collected 08 20 09 Obstruction Point Area, Olympic National Park, Washington

  • subgplatefig
    7 - Steiroxys sp. adult subgenital plate side view, photographed in the lab and labelled.

    Specimen collected 08 20 09 Obstruction Point Area, Olympic National Park, Washington

Dan L. Johnson, University of Lethbridge in Alberta, Canada, has studied and photographed S. trilineata in several populations. A web page he produced includes a photo of the subgenital plate, just ventral to the base of the long ovipositor. (See three-lined shieldback)

The shape of the subgenital plate, especially the square notch seen in our specimens, may be important in identification or may show variation among populations. The notch does not look identical to Johnson’s image.

This page shows the subgenital plate of an adult female, which we collected 09 10 2009 near Obstruction Point Road in the Hurricane Ridge area of Olympic National Park. This characteristic subgenital plate shape can be tracked from the youngest nymphs I’ve collected.