the Elm Sphinx or Four-horned Sphinx
Larvae feed on Elm (Ulmus), birch (Betula), basswood
(Tilia), and cherry (Prunus).
There are both green and brown forms. The four horns near
the head are diagnostic.
This caterpillar is one of the few North American Sphingidae that
feed in large groups. Colouration is distinctive.
are much more spectacular than the moths. Catalpa is the
larval host. questionable;
northwestern range limit in Iowa
WO, Hagen's Sphinx or Osage Orange Sphinx
Larvae feed on osage orange (Maclura pomifera), and they have a granulous appearance with variable amounts of purple
along the oblique white stripes.
Fraxinus, Ligustrum, Quercus, Crataegus and
Chionanthus virginicus are listed as hosts.
In the fifth instar, the spiracular ovals are decidedly red and the
anal horn is off-white to pinkish laterally.
WO, the Pawpaw Sphinx
Larvae feed on pawpaw (Asimina triloba), littleleaf sweetfern
(Myrica aspleniifolia), possum haw (Ilex decidua), and
inkberry (Ilex glabra) as well as Tall Gallberry Holly
Note triangular bump on the thorax.
Larval hosts are various species of beebalm (Monarda), mints (Mentha), bugleweed (Lycopis),
and sage (Salvia). questionable; western range limit in Iowa
The caterpillars are called Tomato Hornworms and each has a black horn at the end of the abdomen.
Larvae feed on potato, tobacco, tomato, and other plants in the
nightshade family (Solanaceae).
Note the red horn and black dots anterior to the white oblique lines.
If you grow tomatoes, you have probably encountered it.
questionable: northern range limit in Iowa
Larvae feed at night, hiding on the underside of stems during the
day. Preferred hosts are common trumpetcreeper (Campsis radicans),
Florida yellow-trumpet (Tecoma stans), lilac
(Syringa species), and passionflower
(Passiflora species). questionable; northern
range limit in Iowa.
WO, the Northern Ash Sphinx or Great Ash
The larvae are pale bluish green. The head has a pair of yellow
lateral bands meeting at the apex. The oblique, lateral stripes are
pale and bordered anteriorly with a darker green.
Larval hosts are ash, lilac, privet, cherry, and quaking aspen.
Larvae hide in the day and feed primarily on cherry, plum, and apple
at night. Larvae have been found on Amelanchier nantuckensis
in Massachusetts and have been reared to pupation in Michigan on
Prunus serotina. Note purple oblique lines.
In the final instar, the black on the head, lateral lines, horn and on abdominal
legs is diagnostic.
Larvae feed primarily on lilac and fringe.
questionable; western range limit in Iowa
Larvae feed on the common snowberry (Symphoricarpos albus)
and on coralberry (S. orbiculatus).
Note the two golden
lines of slightly raised bumps, one just behind the head, the other
on the thorax.
Amorpha juglandis larvae feed upon Walnut and butternut (Juglans),
hickory (Carya), alder (Alnus), beech (Fagus),
hazelnut (Corylus), and hop-hornbeam (Ostrya).
the Modest Sphinx or Poplar Sphinx
Larvae feed on poplars and cottonwood.
Larvae accept willows, birches, and cherries.
I have also found them in the wild on oak in eastern Canada.
Wild cherry species are the favorites as larval foodplants, but eggs
will also be deposited on birches and other forest trees.
There are varying degrees in the amount of red markings along the sides.
Larvae feed upon many forest trees including birches and cherries,
but are expecially fond of poplars and willows. Red markings on sides
vary greatly from specimen to specimen.
See Hemaris comparison
to help distinguish the next two species.
Snowberry Clearwing or Bumblebee Moth
Larval host plants include Snowberry (Symphoricarpos),
honeysuckle (Lonicera), Coralberry, viburnums, Blue Dogbane
(Apocynum) and dwarf bush honeysuckle (Diervilla lonicera).
Horn is black with a yellow base.
WO, the Hummingbird Clearwing
There is also an orangey-pink prepupal form. The lateral line runs
from S1 to the blue horn.
Hemaris thysbe larvae feed on viburnum and related plants.
Larvae feed upon Grape (Vitis), Virginia Creeper
(Parthenocissus quinquefolia) and other vines and ivies
Larvae occur in both a light (green) form and a darker (tan/brown)
form. Note six "segmented" oblique lines.
If you have Grape or Virginia Creeper nearby, then you might encounter
Note the five large white ovals. There are orangey-brown and green
questionable, northwestern Iowa range limit
In additon to Virginia creeper larvae accept Grape (Vitis),
ampelopsis (Ampelopsis), and cayenne pepper (Capsicum).
Larvae are green until the final instar.
WO, the Virginia Creeper Sphinx or the
If you have the
foodplants indicated in the common names, you probably have this
species nearby. The lower wings are orange.
Larvae feed on Virginia creeper (Parthenocissus quinquefolia),
Grape (Vitis), Ampelopsis, and Viburnum.
questionable; northwestern range limit in Iowa
Grape (Vitis), ampelopsis (Ampelopsis), and
Virginia creeper (Parthenocissus) all serve as larval hosts.
The alternating yellow and greyish-green rings across the back
distinguish this larva.
DB, Leafy Spurge Hawk Moth
Larvae feed on leafy spurge. Larvae are also conspicuously colored, with a
pronounced tail or "horn" near rear end.
Young larvae are variously patterned with green, yellow, and black;
older larvae have distinctive red, black, yellow, and white color
pattern. Mature larvae may approach 10 cm in length; when disturbed,
they regurgitate a slimy green liquid.
Now confirmed in Woodbury County,
by Dianne Blankenship.
WO, the Bedstraw Hawk Moth
or Gallium Sphinx
This species is not reported in Plymouth County, but it
might be present.
Larvae come in black and in brown forms and often feed on
Epilobium (fireweed). questionable
WO, the White-lined Sphinx
Larvae are highly varied and feed on a great diversity of plants
including willow weed (Epilobium), four o'clock (Mirabilis),
apple (Malus), evening primrose (Oenothera), elm
(Ulmus), grape (Vitis), tomato (Lycopersicon),
purslane (Portulaca), and Fuschia.
All larvae seem, however, to have the red/black swellings split by
Larvae feed on (Onagraceae) including evening primrose
(Oenothera), gaura (Gaura), and willow weed
Larvae feed at night on grape (Vitis) and ampelopsis
(Ampelopsis) and hide on the bark of their host plants during
the day. Virginia creeper would also be a suitable host.
There is also a dark form
without the green patches. Note the "raised eye", replacing the anal horn.