Subfamily Copiphorinae
coneheaded katydids

Key to families and subfamilies of katydids.
Key to genera of coneheaded katydids (Copiphorinae).

Coneheaded katydids are medium-to-large (24-74 mm), grasshopper-like insects with oversized jaws. They are the only katydids that have the head produced into a pointed or rounded cone that projects beyond the basal antennal segments. Most species have long, narrow forewings and, with the aid of the concealed hindwings, are strong fliers; a few species have abbreviated forewings and are flightless. Four genera and 22 species occur in America north of Mexico. All occur in the eastern United States and only 3 species have been found west of Texas.

Brown/green color dimorphism

All U.S. coneheads occur in two color phases: brown and green. Except for Pyrgocorypha uncinata, in which no green males are known, both males and females are dimorphic. In two other species (Neoconocephalus triops and Bucrates malivolans) the green phase is much rarer among males than females. In most species the proportions of the two phases are similar for the two sexes, but the proportions vary widely among species and among series of the same species collected at different places and at different times. No one has carefully studied the occurrence of brown and green phases in any species of conehead. Such a study would require collection or observation of large numbers of individuals at different places and times by methods that were not biased by the color of the individuals that might be collected or observed.

Little is known of the adaptive significance or the genetic and environmental determinants of the color phases. The adaptive significance is most likely related to protection from diurnal, visually hunting predators, such as many species of birds. Experiments have shown that when such a predator has fed upon prey of one color, it is less likely to capture another individual of the same species if that individual is of a different color. The merits of a conehead being brown or green thus depend not only on the color of the individual's surroundings, which are generally brown and green, but also upon the color of its neighbors and the previous experiences of its visually hunting predators. Anyone who searches for coneheads visually will soon confirm that it is difficult to look for brown and green individuals simultaneously, that the color sought is influenced by the color of previous captures, and that individuals of the other color are less likely to be detected.

Individuals sometimes change color during their development. For instance, all early juveniles of Neoconocephalus and Belocephalus are green, a few become brown during molts to late juvenile instars, and the majority of those that become brown adults change during the final molt. Apparently no one has recorded a conehead molting from brown to green.

J. J. Whitesell (1974) showed that the color of male Neoconocephalus triops is influenced by photoperiod. Green nymphs exposed to 11-hour photoperiods molted to brown adults whereas those exposed to 15-hour photoperiods produced both green and brown adults. Under natural conditions this results in winter males being brown and summer males being dimorphic.

Oviposition

The ovipositors of coneheads are slender, nearly straight, and bear no teeth. Bucrates malivolans, with a blade 35-45 mm long, has the most spectacular egg-laying tool of any U.S. katydid. It and other species that have been seen ovipositing insert their eggs between the stems and sheaths of root leaves of cattails or grasses. Whitesell (1969) reported that Neoconocephalus retusus females chew through grass sheathes about 2 cm above ground level and push the ovipositor down into the sheath through the opening. The ovipositors of Belocephalus species are stouter than those of other genera, but no one has observed their use.

Remarks

Except among short-winged coneheads (Belocephalus), female coneheads are generally much larger than males. In a few species the smallest female known exceeds the largest male. The significance of such discrepant sizes is unexplained.

Coneheads are often easy to find at night-by going to calls of males and by inspecting seed heads of grasses for feeding females. Some species fly to lights. Finding coneheads in the daytime is difficult. In at least two genera (Neoconocephalus and Pyrgocorypha) adults crawl head down in bunches of grass until only their wings and extended hindlegs are visible. In this posture the insect resembles just another green or brown grass blade.

References

Blatchley WS. 1920. Orthoptera of northeastern America. Indianapolis, IN: Nature Publishing. 784 p. Copiphorinae (pp. 502-533) [2638 KB]. (The introductory pages to Blatchley's book are accessible on SINA's home page.)

Brush JS, Gian VG, Greenfield MD. 1985. Phonotaxis and aggression in the coneheaded katydid Neoconocephalus affinis. Physiol. Entomol. 10: 23-32.

Burk T. 1982. Evolutionary significance of predation on sexually signalling males. Fla. Entomol. 65: 90-104. [1277 KB] [Neoconocephalus triops]

Deily JA, Schul J. 2004. Recognition of calls with exceptionally fast pulse rates: female phonotaxis in the genus Neoconocephalus (Orthoptera: Tettigoniidae). Journal of Experimental Biology 207: 3523-3529. [81 KB]

Faure PA, Hoy RR. 2000. The sounds of silence: cessation of singing and song pausing are ultrasound-induced acoustic startle behaviors in the katydid Neoconocephalus ensiger (Orthoptera; Tettigoniidae). J. Comp. Physiol. A. Sens. Neural. Behav. Physiol. 186: 129-142.

Greenfield MD. 1983. Unsynchronized chorusing in the coneheaded katydid Neoconocephalus affinis. Anim. Behav. 31: 102-112.

Greenfield MD. 1993. Inhibition of male calling by heterospecific signals: Artifact of chorusing or abstinence during suppression of female phonotaxis? Naturwissenschaften 80: 570-573. [Neoconocephalus affinis]

Gwynne DT. 1977. Mating behavior of Neoconocephalus ensiger (Orthoptera: Tettigoniidae) with notes on the calling song. Can. Entomol. 109: 237-242. [654 KB]

Heath JE, Josephson RK. 1970. Body temperature and singing in the katydid Neoconocephalus robustus (Orthoptera, Tettigoniidae). Biol. Bull. 138: 272-285.

Hebard.M. 1926. A revision of the North American genus Belocephalus (Orthoptera; Tettigoniidae, Copiphorinae). Trans. Am. Entomol. Soc. 52: 147-186, 2 pl. [2830 KB]

Hebard M. 1939. Studies in Orthoptera which occur in North America north of the Mexican boundary. X. New and critical notes on previously known Tettigoniidae. Trans. Am. Entomol. Soc. 65: 161-183, 3 pl. [Bucrates malivolans] [2021 KB]

Josephson RK. 1985. The mechanical power output of a tettigoniid (Neoconocephalus triops) wing muscle during singing and flight. J. Exp. Biol. 117: 357-368.

Libersat F, Hoy RR. 1991. Ultrasonic startle behavior in bushcrickets (Orthoptera; Tettigoniidae). J. Comp. Physiol. A. Sens. Neural. Behav. Physiol. 169: 507-514. [Neoconocephalus ensiger]

Meixner AJ, Shaw KC. 1979. Spacing and movement of singing Neoconocephalus nebrascensis males (Tettigoniidae: Copiphorinae). Ann. Entomol. Soc. Am. 72: 602-606.

Meixner AJ, Shaw KC. 1986. Acoustic and associated behavior of the coneheaded katydid, Neoconocephalus nebrascensis, Orthoptera: Tettigoniidae. Ann. Entomol. Soc. Am. 79: 554-565.

Nutting WL. 1953. The biology of Euphasiopteryx brevicornis (Townsend) (Diptera, Tachinidae), parasitic in the cone-headed grasshoppers (Orthoptera, Copiphorinae). Psyche 60: 69-81. [Neoconocephalus robustus]

Rehn JAG, Hebard M. 1915. A synopsis of the species of the genus Neoconocephalus found in North America north of Mexico. Trans. Am. Entomol. Soc. 40: 365-413. [5040 KB]

Schul J, Patterson AC. 2003. What determines the tuning of hearing organs and frequency of calls? A comparative study in the katydid genus Neoconocephalus (Orthoptera, Tettigoniidae). J. Exp. Biol. 206: 141-152.

Shaw KC, Bitzer RJ, North RC. 1982. Spacing and movement of Neoconocephalus ensiger males (Conocephalinae: Tettigoniidae). J. Kans. Entomol. Soc. 55: 581-592.

Strohecker HF. 1939. Distributional and taxonomic notes on southeastern Dermaptera and Orthoptera and a new species of Cycloptilum (Gryllidae). Can. Entomol. 71: 169-175. [Belocephalus spp., Pyrgacorypha uncinata, Bucrates malivolans] [731 KB]

Thomas ES. 1933. Neoconocephalus lyristes (Rehn and Hebard) in the Middle West. Ann. Entomol. Soc. Am. 26: 303-308. [518 KB]

Walker TJ. 1975. [See correction at end of references] Stridulatory movements in eight species of Neoconocephalus (Tettigoniidae). J. Insect Physiol. 21(3): 595-603. [864 KB]

Walker TJ. 2014. A new North American species of Bucrates (Orthoptera: Tettigoniidae: Conocephalinae: Copiphorini). Journal of Orthoptera Research 23(1): 69-73. [1379 KB]

Walker TJ, Greenfield M. 1983. Songs and systematics of Caribbean Neoconocephalus (Tettigoniidae Orthoptera). Trans. Am. Entomol. Soc. 109: 357-389.  [3905 KB]

Walker TJ, Whitesell JJ. 1978b. A new species of conehead from the Florida Everglades (Orthoptera: Tettigoniidae: Neoconocephalus). Entomol. News 89(1&2): 27-32. [Neoconocephalus pakayokee]  [453 KB]

Walker TJ, Whitesell JJ. 1978a. Neoconocephalus maxillosus: a Caribbean conehead in south Florida (Orthoptera: Tettigoniidae). Fla. Entomol. 61(1): 1-3.  [220 KB]

Walker TJ, Whitesell JJ, Alexander RD. 1974. The robust conehead: two widespread sibling species (Orthoptera: Tettigoniidae: Neoconocephalus "robustus"). Ohio J. Sci. 73(6): 321-330.  [1089 KB]

Whitesell JJ. 1969. Biology of United States coneheaded katydids of the genus Neoconocephalus (Orthoptera: Tettigoniidae). MS thesis. Gainesville, FL: University of Florida. 72 p.

Whitesell JJ. 1974. Geographic variation and dimorphisms in song, development, and color in a katydid: field and laboratory studies (Tettigoniidae, Orthoptera). PhD dissertation. Gainesville, FL: University of Florida. 75 p. [Neoconocephalus triops]

Whitesell JJ, Walker TJ. 1978. Photoperiodically determined dimorphic calling songs in a katydid. Nature 274(5676): 887-888.  [924 KB] [Neoconocephalus triops]

Correction to Walker 1975, J. Insect Physiol 21:595-603:
Darryl T. Gwynne, Dept. Zoology and Entomology, Colorado State University, Fort Collins, Colorado, recently showed me that the song of N. ensiger ends in a peculiar cricket-like pulse of sound and suggested that the final rapid closing movement of the tegmina might produce it. I have reanalyzed my films and conclude that his interpretation is correct. T. J. Walker, April 1975