Caterpillars of Pacific Northwest
Forests and Woodlands
Photo Key to Species
- Group A-1 -- One pair of midabdominal prolegs, on segment A6. All of these species are Geometridae.
- Group A-1a -- Body wall with lateral projections
- Group A-1b -- Subgroups: Body wall smooth
- Distinct spiracular line
- Dorsum color different than subspiracular area
- Distinct subdorsal longitudinal lines
- Middorsal area with a stripe or dots
- Body with distinct patches of color
- Body without distinct markings
- Group A-2 -- Two or Three Pairs of Midabdominal Prolegs
- Prolegs on A5 smaller than those on A6
- Prolegs on A5 same size as those on A6
- Group B-1 -- Without Dense Patches of Hairs
- Group B-1a -- Subgroups: Body wall with swellings
- Middorsal horn absent on A8
- Middorsal horn present on A8
- Group B-1b -- Subgroups: Body wall smooth, except monarch butterfly
- Colors in rings
- Straight longitudinal lines
- Wavy longitudinal lines
- Irregular middorsal markings
- Spots, or streaks, or reticulated
- No distinct markings
- Group B-2 -- With Dense Patches of Hairs
- Group B-2a -- Subgroups: Hairs different lengths
- Middorsal tufts of short, dense hairs
- Sublateral long, dense hairs
- At least half covered in long hairs
- Less than half covered in long hairs
- Group B-2b -- Subgroups: Hairs very short
- Humped in profile, head concealed
- Not humped in profile, head exposed
- Group B-3 -- With Sclerotized Spines
- Pupae of Lepidoptera
- Larva of a Sawfly
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