Montana Field Guide

The following is taken from Rehn and Hebard (1914), Blatchley (1920), Helfer (1971), Vickery and Kevan (1985), Bland (2003), Capinera et al. (2004), Elliott and Hershberger (2007), and Himmelman (2009). This katydid is so named due the extremely long ovipositor of the female which can be longer than its body. The body color is grass-green (brown forms are known to occur) with a pale stripe extending from the cone tip and across the head and lateral edge of the pronotum. Also, a pale stripe occurs diagonally from behind the eye onto the lateral side of the face. The upper half of the ventral surface of the projecting cone (fastigium) is edged in black (see illustration). The hind tibia and the female ovipositor is brown. When disturbed, this species reacts in a variety of ways. It may sit still, or move to the opposite side of a plant stem, or quickly fall headfirst into dense vegetation and remain motionless with their fastigial cone embedded in the ground. In open areas, males often escape by taking flight and it has been noted that females are more difficult to find.

Calling song description
Verbal descriptions are: (1) “Stridulation consists of rapid, lisping pulses of about five per second (Bland 2003). (2) “The stridulation sounds like a rapid succession of pulses, ‘tsip, tsip, tsip, tsip,’ at about 10 per second…Opening the tegmina is silent, but closure produces a train of rapid decay pulses ending with an intense prolonged pulse” (Vickery and Kevan 1985). (3) “A series of rapid, lisping buzzes, like a fast-moving train. Calls begin at dusk and go well into the night” (Himmelman 2009). (4) “A rapid train of brief raspy notes…given at a rate of five to ten notes per second, depending on the temperature: tst-tst-tst-tst-tst-tst…Song is very loud and easily heard as one drives along country roads in late summer or early autumn. Starts singing at dusk and continues throughout night unless the temperatures drop too low. Males often sing in unison on cooler nights” (Elliott and Hershberger 2007). (5) “…This insect has but a single song and stridulates only at night, or during cloudy weather. It begins its song as soon as the sky is obscured or the sun near the horizon. It commences with a note like brw, then pauses an instant and immediately emits a rapid succession of sounds like chwi at the rate of about five per second, and continues them for an unlimited amount of time…its note to the syllable ‘ik-ik-ik,’ as if sharpening a saw, enlivening the low bushes and particularly the corn-patch, as it seems to…delight in perching near the top of a cornstalk and…giving…its song…” (Blatchley 1920).

This species overwinters in the egg stage. The nymphs hatch in May-June. Adults occur from mid-July to mid-October, depending upon killing frost occurrence (Vickery and Kevan 1985, and Bland 2003).

The following comes from Rehn and Hebard (1914), Blatchley (1920), Helfer (1971), Vickery and Kevan (1985), Bland (2003), Capinera et al. (2004), Elliott and Hershberger (2007), and Himmelman (2009). The body length to the end of forewings is 24-26 mm for males, and 28-30 mm for females. The fastigium (anterior tip of the head, see illustration) for males is 3 mm, and females 3.2-3.5 mm. The pronotum, male and female, is 7-7.5 mm and the tegmina (forewing) for males is 37-42 mm, and females 44-48 mm. The hind femur for males is 20-21 mm, and females, 22-23 mm. The female ovipositor is 27.5-33 mm.

Due to this species’ size, morphology, present limited range and being the only species of Neoconocephalus occurring in the state, there should be little confusion with other katydids.

This species inhabits weedy fields, pastures, roadsides, prairies and wetland edges, and tends to favor habitats with moist conditions or water nearby. This species will also inhabit cornfields, perching 6-7 feet above the ground on a corn stalk or tassel, from which it often sings (Cantrall 1943, Vickery and Kevan 1985, and Bland 2003).

The Sword-bearing Conehead Katydid mostly feeds on seeds of grasses, less frequently on flowers, grass blades and parts of sedges (Bland 2003).

When a sexually responsive female is attracted to a singing male, she moves vertically toward him by walking or occasionally flying. When the male detects her, he orients toward her, moves a few inches in her direction, and upon contact on a grass stem the pair move together and attenuate (touching with their antennae) each other. Copulation occurs quickly as the male arches his abdomen and they engage genitalia. He usually continues to stridulate until physical contact is made, his song becoming sporadic and stops upon full copulation. The copulating pair are positioned on the grass stem with the male pointed head downward and the female upward. Both the male and female use the tarsi of the first two pair of legs to grasp each other’s tegmina and supporting vegetation. Often the male grasps the female’s ovipositor. During the first few minutes of copulation, the male makes rhythmic movements of his subgenital plate and abdomen against the base of the female’s ovipositor passing his spermatophore. Copulation lasts from 27-68 minutes, usually the female initiates separation, upon which no spermatophore is visible (Gwynne 1977).