Conocephalus (Xiphidion) angustifrons ( Redtenbacher, 1891 )

Piotr Naskrecki, 2000, Katydids of Costa Rica / Vol. 1, Systematics and bioacoustics of the cone-head katydids (Orthoptera: Tettigoniidae: Conocephalinae sensu lato)., Philadelphia, PA: The Orthopterists Society at the Academy of Natural Sciences of Philadelphia, : 14-16

Conocephalus (Xiphidion) angustifrons ( Redtenbacher, 1891)

Figs. 1 C, 2E, 2J, 36A, 39B, 39J, 52C-D, Map 1

1891 Redtenbacher, Monogr. Conoceph.: 498 >> Xiphidium ; type locality: Colombia: Tolima and Sta Fe de Bogota; type depository: Naturhistorisches Museum, Vienna, Austria – male and female syntypes

1906 Kirby, Syn. Cat. Orth. 2: 282. >> Anisoptera 1915b Rehn and Hebard, Trans. Amer. Ent. Soc. 41: 260 >> Conocephalus (Xiphidion)

Diagnostic description.— General characteristics as described above; most individuals in the Costa Rican population mesopterous ( Fig. 36 A), rarely macropterous.

Stridulatory file of male 1.06 mm long, with 40 teeth, maximum width of file 50 μm ( Fig. 39 J); teeth of file thick, peg-like, more densely arranged at proximal end of file. Left (upper) mirror of stridulatory apparatus as in Fig. 1 C, shorter than eye diameter. Fastigium of 1/2 to 3/4 as wide as scapus. Outer ventral edge of hind femur armed with 1-4 minute, black spines. Male cercus as in Fig. 39 B; ovipositor distinctly shorter than hind femur (ratio ovipositor/hind femur 0.62-0.71), weakly upcurved ( Fig. 2 E).

Coloration.— Coloration unique, in live individuals head and anterior portion of pronotum aquamarine green or teal, posterior part of pronotum, thoracic terga and first four abdominal terga emerald green; remaining portion of abdomen of male bright orange-red, that of female reddish-brown; all femora brown, hind knees dark brown; fore and mid tibia emerald green, hind tibia dark green to brown. Dorsum of head and pronotum with wide, dark band, typical of most species of the genus ( Fig. 36 A). Coloration deteriorates considerably in preserved specimens but most of them still retain dark bluish-green coloration, unlike any other species of Conocephalus .

Measurements.— Table 2 .

Bioacoustics.— The call of C. angustifrons consists of a series of short chirps, produced at the rate of about 1.4- 2.0 per second (at 26°C) ( Fig. 52 C). Each chirp lasts 92- 124 ms (avrg. 116±10.3, n=10) and consists of 3-4 wingstrokes (opening and closing), with the first wingstroke being incomplete ( Fig. 52 D). Typically of the genus, the call is low Q, with most energy within the audible part of the call allocated between 6.5-16 kHz.

Remarks.— This species is known from the Atlantic portion of Costa Rica ( Map 1 ), Panama, and Colombia. It is one of the most distinctive species of the genus and cannot be confused with any other species of Conocephalus in Costa Rica. Conocephalus angustifrons seems to be active mostly at night although males also stridulate during the day. This species appears to be predaceous, successfully hunting insects of nearly equal body size (e.g., katydids of the genus Phlugis ).

Material examined.— COSTA RICA: Cartago Prov., 2 mi SE Turrialba (grounds of Inst. Interamer. de Sci. Agricolas), 1 - 3 October 1961 (coll. Hubbell, Cantrall, Cohn) - 5 males, 1 female ( UMMZ); Monumento Nacional Guayabo, A.C.A.C. Amistad, 15 July 1994 (coll. G. Fonseca) - 1 male ( INBio); Quebrada Segunda Ref., Nac. Fauna Silv. Tapantí, elev. 1250 m, 15 April 1992 (coll. R. Vargas) - 1 female ( INBio); Heredia Prov., Braulio Carillo N. P., Estac. El Ceibo, elev. 400 - 600 m, 15 December 1989 (coll. R. Aguilar and M. Zumbado) - 2 males ( INBio); Puerto Viejo, La Selva Biological Station, elev. 50 - 150 m, 10° 26' N, 84° 1' W, 1 - 4 April 1994 (coll. P. Naskrecki) - 1 male ( INBio); same locality, elev. 50 - 150 m, 10° 26' N, 84° 1' W, 13 April - 10 May 1998 (coll. P. Naskrecki) - 2 males ( INBio); Limón Prov., Estac. Hitoy-Cerere Res. Biol. Hitoy Cerere, Río Cerere, elev. 200 m, 15 December 1990 (coll. G. Carballo) - 1 male ( INBio); same locality, elev. 200 m, 15 April 1991 (coll. G. Carballo) - 1 male ( INBio); same locality, elev. 100 m, 15 June 1991 (coll. A. Moreno) - 1 female ( INBio); same locality, elev. 100 m, 15 June 1991 (coll. G. Carballo) - 1 male, 1 female ( INBio); Los Diamantes (1 km E of Guápiles), 26 - 27 January 1967 (coll. I.J. Cantrall) - 10 males, 6 females ( UMMZ); Saturno Farm, Estrella Valley, elev. 30.48 m, 12 September 1923 - 2 males ( ANSP); PANAMA: Canal Zone, Barro Colorado Island, 20 January 1967 (coll. I.J. Cantrall) - 1 female ( UMMZ).

Figures

FIG. 1. Costa Rican Conocephalus spp. A. C. saltator - habitus; B-F: male pronotum, dorsal view. B. C. saltator, C. C. angustifrons, D. C. ictus, E. C. cinereus, F. C. magdalenae.

FIG. 2. Costa Rican Conocephalus spp. A. C. cinereus - habitus; B-F: ovipositors. B. C. magdalenae, C. C. cinereus, D. C. ictus, E. C. angustifrons, F. C. saltator; G-K: titillators. G. C. magdalenae, H. C. cinereus, I. C. ictus, J. C. angustifrons, K. C. saltator

FIG. 3. Orchelimum fraternum. A. male - habitus, B. male face, C. male head and pronotum, dorsal view, D. male subgenital plate, ventral view, E. titillators, F. ovipositor.

FIG. 35. Costa Rican species of Podacanthophorus. A. P. alas - male face, B-F. head and pronotum, dorsal views: B. P. alas - female, C. P. alas - male, D. P. vargasi - male, E. P. maylinae - male, F. P. nelciae - female; G-I. head and pronotum, lateral views: G. P. vargasi - male, H. P. maylinae - male, I. P. nelciae - female; J. P. nelciae - ovipositor; K-N. left hind femora, outer views: K. P. alas, L. P. vargasi, M. P. maylinae, N. P. nelciae.

FIG. 36. Costa Rican species of Conocephalinae s. l. A. Conocephalus angustifrons - male, B. Caulopsis cuspidata - female, C. Acantheremus colwelli - male, D. Vestria punctata - male and female, in copula, E. Copiphora hastata - male, F. Podacanthophorus vargasi - female, G. Copiphora rhinoceros - male eating a snail, H. Subria sylvestris - male, brown form.

FIG. 39. Cerci and stridulatory files of species of Conocephalus. A-H. male left cerci, dorsal views: A. C. saltator, B. C. angustifrons, C. C. magdalenae, D. C. fasciatus, E. C. ictus, F. C. cinereus, G. C. spinosus, H. C. cf. spinosus; I-J. male stridulatory files: I. C. saltator, J. C. angustifrons.

FIG. 52. Oscillograms of male airborne calls of Costa Rican species of Conocephalus. A. C. saltator, B. ditto, 0.5 s fragment, C. C. angustifrons, D. ditto, 0.5 s fragment, E. C. cinereus, F. ditto, 0.5 s fragment, continuous part, G. ditto, 0.5 s fragment, slow part.

MAPS 1 - 6. Distribution of species of Conocephalinae s. l. in Costa Rica. 1. Conocephalus angustifrons, C. cinereus, 2. Conocephalus saltator, C. ictus, 3. Conocephalus magdalenae, Orchelimum fraternum, Lipotactomimus rowelli, 4. Lirometopum coronatum, Acantheremus colwelli, 5. Copiphora rhinoceros, C. cochleata, C. brevicauda costaricensis, 6. Copiphora hastata, C. cultricornis, C. ottei.