Florissant - Fossil Ecosystems of North America: A Guide to the Sites and their Extraordinary Biotas - page 208

Odonata: dragonflies and damselflies.
Giant Protodonata existed in earlier
times (Chapter 7), but they became
extinct and by the Eocene the true
Odonata were similar in size to those
alive today. Dragonflies, like mayflies,
are rather primitive in that they cannot
fold their wings over their backs, whereas
damselflies ( 233 ) can. In flight, Odonata
move their fore- and hindwings up and
down asynchronously, whereas in other
insects that use both pairs of wings for
flight, such as bees, wasps, butterflies,
and moths, the two pairs of wings move
up and down together.

The neopteran insects, which can fold
their wings and use them synchronously
in flight, include all higher insects.
Orthoptera (grasshoppers, locusts,
crickets, and katydids) occur at Florissant,
and probably provided the sounds
of summer meadows and night-time
chirping we are familiar with today.
Grasshoppers are commonest, yet we think
of them today as creatures of grasslands.
Either they inhabited woodlands or there
were patches of meadow in the Florissant
forest. Twelve species of Dermaptera
(earwigs) have been described from
Florissant. In this order the forewings have

232

232 Pod of the legume described
as ProsopisFabaceae NHM.
Length 64 mm 2.5 in.

233

233 Damselfly Odonata NHM.
Length of forewing 36 mm 1.4 in.