Conocephalus (Perissacanthus) doryphorus ( Karny, 1907 ) Greco-Spingola & Braun, 2019

Greco-Spingola, Silvana & Braun, Holger, 2019, Clarifying the identity of the Uruguayan meadow katydid Conocephalus doryphorus (Orthoptera: Tettigoniidae: Conocephalini), Zootaxa 4688 (1), pp. 147-150 : 147-148

Conocephalus (Perissacanthus) doryphorus ( Karny, 1907) comb. nov.

Specimens: URUGUAY: Rivera, Sierrra de la Aurora: 4 males and 2 females, 12/I/1961 (FCE-TE 0710); 2 males, 12/ I/1961, (FCE-TE 0711); 1 female, 15/I/1961 (FCE-TE 0715); 1 male, 11–12/I/1961 (FCE-TE 0716); Flores, Paso Pinto, Arroyo Pinto : 4 males and 2 females, 18–19/III/1960 (FCE-TE 0712) ; 2 females, 18–19/III/1960 (FCE-TE 0713) ; 1 male, 18–19/III/1960 (FCE-TE 0718); Durazno, Arroyo del Cordobés : 1 male, 27/I/1967 (FCE-TE 0714) ; Florida, Casupá : 2 females, 20/III/1958 (FCE-TE 0080, -0081) ; 1 male, 20/III/1958 (FCE-TE 0082) ; San José, Arroyo Mauricio : 1 female , 13–15/II/1963 (FCE-TE 0717); ARGENTINA: 2 males, Buenos Aires, Parque Provincial Pereyra Iraola, near crossing of highway Buenos Aires–La Plata over Arroyo Pereyra , 24/II/2019 (MLP-OR-3181, -3182).

Diagnosis: A brachypterous meadow katydid, tegmina in males slightly longer than pronotum, in females shorter than pronotum (in C. strictoides males they are more than twice as long as and in females of about same length as pronotum). In dorsal view, the fastigium is constricted before the tip. Hind tibia with five spurs at the tip (no interno-dorsal spur, Fig. 1E ). Ovipositor only as long as hind femur (13–14 mm, in C. strictoides 22–24 mm).

Redescription: In life mostly green with dark dorsal band along head, pronotum, and abdomen ( Fig. 1B,C,D ); the latter in males distally reddish to orangish ( Fig. 2E ). Fastigium tip slightly elevated, almost as wide as scapus, before tip narrowed to pedicellus width. Rear margin of lateral lobe of pronotum straight except for translucent convexity right at the margin (no humeral sinus). Tegmina light brownish, in males about 1.5 times as long as pronotum and with relatively large, transparent stridulatory area, in females distinctly shorter than pronotum. Legs green, fore tibiae with short black dorsal stripe between ear openings (slightly more distinct than in other Neotropical Conocephalus species), hind femur without spines, fore and middle tibiae with six pairs of ventral spinules. Male cerci with ventro-internal spinule at the base ( Fig. 2E ), base internally concave with very small conchate crest at dorsal margin of this concavity, distal half of cerci bent outward and dorsoventrally depressed. Ovipositor of females almost straight, slightly shorter than body ( Fig. 1B ). Measurements in table below.

The presently documented distribution encompasses northern, central and southern Uruguay as well as the northeast of Buenos Aires Province (a map with geo-referenced records is available on OSF). As other Conocephalus species, C. doryphorus lives in meadows.

Song: The two recorded males produced calling sequences with durations from only 4 or 5 seconds up to 25 seconds or longer, separated by pauses of 1 to 2 minutes. They showed calling activity at day and night. The species probably can call even more constantly as is typical of the genus. These calling sequences consist of continuously repeated syllable groups (five are shown in Fig. 2A ) of variable syllable number and length. The illustrated male made fairly uniform groups of around 700 milliseconds at 23–24°C, mostly each with the first syllable slightly louder than the rest. The latter was not the case in the other male, and it showed more variable and partly much longer syllable groups. Syllable repetition rate is about 27–30 per second at this temperature. Each syllable consists of a very soft hemisyllable, probably produced at the opening stroke of the tegmina, and a loud hemisyllable, probably made at the closing stroke, and consisting of a decrescending series of rapidly decaying impulses corresponding to individual tooth scraper impacts ( Fig. 2B,C ). The carrier frequency spectrum is very broad, ranging from 20 kHz to around 70 kHz, with most energy between 20 and 30 kHz. The sympatric C. longipes , a species that occurs syntopic with C. doryphorus at the locality in Argentina (Parque Pereyra), does not show the grouping into syllable groups, but repeats the syllables uniformly (two recordings from 2012 are available on OSF).

Figures

FIGURE 1. Conocephalus doryphorus, A holotype, B adult female (FCE-TE 0081), C,D adult male (FCE-TE 0082) (all to same scale), E internal view of tip of right hind tibia (male), F the same of a male of C. longipes (from La Plata, MLP-OR-3117), showing the interno-dorsal spur which is absent in C. doryphorus (the dark structure visible in this place in E is the dorsal margin of the tarsomere).

FIGURE 2. Conocephalus doryphorus specimen MLP-OR-3182 as found in the field and illustrations of its calling song recorded in the evening of the same day at 24.4°C: A complete short calling sequence consisting of five syllable groups, B onset of last group from A, C first syllable from B, D linear spectrogram, E live male in dorsal view, insert: close-up of left cercus showing basal spine.