Order Protura

No common name

described by Silvestri 1907

Greek, protos = first; oura = tail

Class and Order of entognathous Hexapoda

Cosmopolitan in distribution and consisting of about 500 nominal species, placed in 4-8 families

Protura Anatomy

1. Prognathous
2. Lance-like mandibles; well developed maxillary and labial palpi
3. No compound eyes (perhaps one pseudocellus = cimple eye; detects light intensity)
4. No antennae

1. Weakly developed (segments visible)
2. Forelegs often held up, extended in front of body and used as antennae, not used for walking

1. 12 segments in adults
2. Sterna 1-3 with small eversible styli.
   1. Evolutionary significance: Styli show early hexapod development. Serial metamerism thought to be at play.
   2. Ecological significance: Abdominal appendages have eversible sac-like vesicles for absorbing water from the substrate.
3. Cerci absent.
4. Malpighian tubules present

Protura Biology & Ecology

Biology

1. Anamorphosis (Greek, ana = throughout; morphosis - shaping). The evolution of one type from another through a gradual series of changes. Increase in number of segments during moulting in an insect after emergence from the egg.
   1. Found in Protura and regarded as a primitive condition in metamorphosis.
   2. Eclose with 9 abdominal segments; additional segments added at moults.
2. Some respire with tracheae; some respire cutaneously.
3. Defensive glands on side of abdominal segment 8.

Ecology

1. Rare hexapods whose ecology is poorly known.
2. Inhabit loose, moist soil; under bark, in thick moss, in decomposing logs.
   1. Especially rich in humus.
   2. No digging legs; travel through crevices in soil.
3. Feeding
   1. Stylet-like mouthparts (sucking).
   2. Feed on mycorrhizae of trees.
   3. May also feed on decomposing organic matter & fungal spores.

thanks to University of Queensland

• NCSU
• UF Featured Creatures
• Protura - Discoverlife