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 Major Groups | Insecta (insects) | Ephemeroptera (mayflies) | Prosopistomatidae


Major Group: Insecta
Order: Ephemeroptera
Family: Prosopistomatidae
Genus: Prosopistoma
Species: pearsonorum

This family is represented in Australia by a single species, Prosopistoma pearsonorum.

Descriptive Features:

  • head broad with convex upper surface, width 2.4 X length
  • eyes depressed
  • 5-segmented antennae short, less than 1/4 width of head
  • labium modified to form flat ventral shield
  • body form extremely modified, oval in dorsal view, dorsal surface strongly convex, ventral surface flat
  • mesonotum forms a carapace over thorax and abdomen as far as segment 7, maximum width of mesonotum slightly longer than length of medial suture
  • 6 abdominal gills, not visible from above
  • legs not well developed with tarsi reduced and delicate
  • caudal filaments (of subimago) short, subequal,
  • Total length: 4.5 mm

    Prosopistoma pearsonorum

    Taxonomic Checklist:
    Prosopistoma pearsonorum
    Campbell & Hubbard

    Distribution: N Qld

    Sensitivity Rating: SIGNAL grade 4

    Functional Feeding Group: unknown

    Ecology: Instream habitat: Prosopistomatid nymphs have only been found in inaccessible areas of rapidly flowing tropical streams, such as large rocks or boulders in deep water. They were collected in drift net samples.
    Feeding ecology:
    Life history: Tiny eggs (150 x 100 Ám) have been collected from a subimago female. Eggs are roughly spherical, evenly covered with knob-like coiled threads


    Information Sources: Dean & Suter 1996, Campbell & Hubbard 1998 

    Sclerocyphon maculatus 

    Prosopistoma may be confused with Sclerocyphon (Coleoptera: Psephenidae), distinguished by body segmentation.