1. Shield-backed crickets (Decticini: Anabrus and Pediodectes).
a. Pronotum shiny, covering wings, about ˝ of body length.
b. Front tibiae with one or more apico-dorsal spines.
c. Body length of adults (excluding ovipositor) > 4 cm.
Note: Members of the genus Pediodectes have not been systematically revised in modern times, and the differences and names used here are based upon literature only (Caudell 1907, Hebard 1925).
A. Prosternum without spines.
Anabrus simplex
B. Prosternum with a pair of spines.
Pediodectes spp.
a. Male: cercus with inner tooth longer than remaining dislal lobe. Female: ovipositor > 2/3 length of hind femur.
b. Male: cercus with uncinate, acute inner tooth; female: ovipositor subequal to length of hind femur. Pronotum smooth.
Pediodectes stevensonii
b.’ Male: cercus with blunt to slightly rounded inner tooth; female: ovipositor 2/3 length of hind femur. Pronotum with a well demarked transverse sulcus.
Pediodectes haldemanii
a.’ Male: cercus with distal lobe beyond tooth, longer than inner tooth. Ovipositor < length of hind femur.
Pediodectes nigromarginata
2. Large cone-headed grasshoppers (Coprophorinae: Neoconocephalus) .
a. Head with pointed, conical projection beyond antennal bases.
b. Ovipositor blade-like and straight.
c. Wings extend well beyond abdomen (except ovipositor).
d. Body length > 2.5 cm.
A. Fastigum black beneath.
Neoconocephalus lyristes
B. Fastigum with a ventral black crescent.
Neoconocephalus ensiger
C. Fastigum without black on ventral surface.
Neoconocephalus robustus
3. Small cone-headed grasshoppers (Conocephalinae: Conocephalus, Orchelimum).
a. Dorsum with a pale edged brown median stripe.
b. Head with a rounded or acute projection between antennae.
c. Ovipositor blade-like, weakly upturned or straight, with pointed apex.
d. Wings variable, often brachypterous and shorter than abdomen or pronotum.
A. Wings extending well beyond abdomen, ovipositor curved upwards, male with subanal plate ‘V- or U- shaped’ (Orchelimum).
a. Ventro-lateral hind femur with a few distal spines.
b. Hind tibiae black.
Orchelimum nigripes
b.’ Hind tibiae green to brown.
Orchelimum silvaticum
a.’ Ventro-lateral hind femur without spines.
b. Face green with a vertical red-brown stripe.
Orchelimum concinnum
b.’ Face umber brown, body length > 2 cm.
Orchelimum campestre
b." Face green, may be flecked with red-brown.
c. Hindwings extend beyond hind femur by about 1/4 of femur length.
Orchelimum delicatum
c. Hindwings only slightly if at all longer than hind femur.
d. Posterio-lateral margin of pronotum incurved and covering spiracle.
Orchelimum vulgare
d.’ Margin of pronotum not incurved, spiracular chamber visible.
Orchelimum gladiator
B. Wings subequal to abdomen or brachypterous, if macropterous, then ovipositor straight (female) and subanal plate with a nearly straight posterior margin (male) (Conocephalus).
a. Ventral surface of hind femur with one or more spines.
b. Abdomen black laterally, pronotum bright green. Ovipositor about as long as abdomen.
Conocephalus nigropleurum
b.’ Pronotum and abdomen brownish yellow. Ovipositor longer than body.
Conocephalus attenuatus
a.’ Ventral surface of hind femur without spines.
b. Distal hindtibia with one spur (calcar) on inner margin, wing length < length of pronotum.
Conocephalus saltans
b.’ Distal hindtibia with two spurs (calcariae) on inner margin.
c. Cercus apically conical, ovipositor curved or longer than hind femur.
d. Cercus length proximad of inner tooth subequal to length from inner tooth to apex; ovipositor curved, length < hind femur. Southern South Dakota.
Conocephalus nemoralis
d.’ Cercus length proximad of inner tooth ˝ that from inner tooth to apex; ovipositor straight, length > hind femur. Southeastern North Dakota, southward
Conocephalus strictus
c. Cercus apically flattened, ovipositor straight, < length of hind femur.
d. Wings longer than abdomen.
Conocephalus fasciatus
d.’ Wings shorter than abdomen.
Conocephalus brevipennis
4. Katydids (Scudderia, Amblycorypha, Pterophylla).
a. Fastigum not projecting between antennal bases.
b. Wings extend beyond abdomen.
c. Dorsum lacking a median brown stripe.
d. Ovipositor blade-like, upturned, rounded apically with serrate edges.
A. Tegmina oval, with a series of parallel veins along costal margin (fenestrate).
Pterophylla camelifolia
B. Tegmina not as above, space between antennal bases wider than the width of a single antennal base.
a. Hind femur about as long as tegmina, anterior edge of pronotum straight to weakly notched at mid line.
Amblycorypha rotundifolia
a.’ Hind femur 2/3 length of tegmina, anterior edge of pronotum with a small tubercle at midline.
Microcentrum oblongifolia
C. Tegmina not as above, space between antennae narrower than with of an antennal base (Scudderia).
--Note, the key below is for males, a few hints for distinguishing females are included. Females are best told by association with males and locality.
a. Male with supra-anal plate crenulate, not projecting posteriad nor ‘Y shaped’, female with ovipositor evenly curved upward.
Scudderia septentrionalis
a.’ Male with ‘Y shaped’ supra-anal plate, female with ovipositor abruptly curved upward.
b. Supra-anal plate with posterior notch deeply ‘U shaped’, the surrounding arms inflated.
Scudderia furcata
b.’ Supra-anal plate with posterior notch broader than the surrounding arms which are laterally flattened. Ovipositor weakly arched along dorsal edge near base.
Scudderia texensis
b." Supra-anal plate with posterior notch an open ‘V’, surrounding arms neither inflated nor laterally flattened.
c. Surrounding arms evenly flared outward.
Scudderia pistillata
c.’ Surrounding arms with both an outer angle and posteriorly projecting lobes.
Scudderia curvicauda