Chlorocanta Chatfield-Taylor, 2023

Cole, Jeffrey A., Chatfield-Taylor, Will, Smeds, Elliott A., Cooley, John R., Gonzalez, Valorie A. & Wong, Caressa, 2023, Phylogeny of North America’s largest cicada radiation redefines Tibicinoides and Okanagana (Hemiptera: Auchenorrhyncha: Cicadidae: Tibicininae), Zootaxa 5346 (5), pp. 501-531 : 516-518

Chlorocanta Chatfield-Taylor, 2023 gen. nov.

Fig. 8 (A. dorsal habitus, B. male genitalia, right lateral view, C. male genitalia, dorsal view, D. female genitalia, ventral view, E. timbal)

Type species: Okanagana viridis Davis, 1918 , here designated

Included species: Chlorocanta viridis ( Davis, 1918) comb. n.

Type Locality: Holotype male is from O’Reilly, Bolivar County, MS, 10-VII-1917. The holotype is in the American Museum of Natural History ( AMNH) and the allotype is located at the Mississippi Entomological Museum , Mississippi State University ( Sanborn & Heath 2017).

Etymology: From the Greek khlōrós, meaning “pale green”, in reference to the uniform green coloration of this genus, and Latin cantus, meaning “song” or “singing”. Feminine.

Distribution: Chlorocanta viridis is found in the southeast United States. It is confined to deciduous forests and may be associated with elm ( Ulmus ; Hill & Marshall 2013). It is also known to come to lights unlike related New World Tibicininae . Its range extends east to near the Mississippi / Alabama border, west to Houston, Texas, north into the southwest corner of Tennessee, and there are several records from southeast Oklahoma.

Description: A medium-sized cicada that is most notable for the bright green coloration on the entire body of both sexes. The type species C. viridis was recently treated in detail (under Okanagana viridis ) by Hill and Marshall (2013) and this description of Chlorocanta was aided in part by their paper.

Head: The width of the head across the eyes extends distinctly past apical pronotal margin. The clypeus is weakly produced and rounded, lacking a strong clypeal suture. The vertex has a depression along the midline but lacks a strong epicranial suture. Thorax: The lateral pronotal margins are subquadrate with the anterior margin convexly curved and the posterior margin sinuate. The apical angles of the pronotum are pointed and the humeral angles are rounded and not strongly pronounced. The center of the pronotum is broad, without a clear longitudinal sulcus. There are two bilateral fissures on each side of the pronotum that run inwards towards the center of the pronotum at an anterior-posterior angle. The cruciform elevation is located directly anterior to the hind margin of the mesonotum. The mesonotum is unmarked. The posterior edge of the metanotum is visible. Wings: Both fore and hind wings are hyaline with green venation. The fore wing length is 2.86–2.99 times the width, with 8 apical cells. The trapezoidal-shaped radial cell reaches the costal node halfway along length of costa, and the ratio of apical cell to ulnar cell length is approximately 1:1. The hind wing has 6 apical cells with a typical branched CuA vein ( Fig. 8A ). Legs: Metacoxa with a meracanthus with a distinct triangular shape, equal in length to the coxa. Metatibiae with spines, all other tibiae without spines. Abdomen: In males the timbals are completely exposed with the timbal membrane having two long and two short ribs ( Fig. 8C ; Hill & Marshall 2013) The tergites are a uniform green and the sternites are a paler yellowish-green compared to the rest of the body.

Male Genitalia: Sternite VII is twice the length of epipleurite VII and flattened at the tip. Sternite VII covers the base of sternite VIII. Sternite VIII is short, triangular, and tapering towards the tip with little curvature. The uncus is not hooked at the tip. The dorsal margin of the uncus is longer than the ventral margin, which curves up to form a distinct point as in many Okanagana .

Female Genitalia: Sternite VII has broad, almost triangular primary notch with slight bulging to the lateral margins and, contrary to Davis (1918), has a distinct secondary notch. The sides of sternite VII form rounded apical prongs.

Diagnosis: Chlorocanta is a North American cicada with the hind margin of the metanotum not hidden by the mesonotum, combined with a trapezoidal-shaped radial cell that reaches the costal node situated halfway along length of costa, characters that Chlorocanta shares with Okanagana , Tibicinoides , and Hewlettia gen. nov. If collection data is available, Chlorocanta is the only cicada with the above combination of characters within its range. If sufficiently preserved, the bright green coloration is enough to differentiate this genus from both Okanagana and Tibicinoides , however specimens of Chlorocanta often fade to a paler yellow which may confuse this single diagnostic feature ( Hill & Marshall 2013). Male Chlorocanta possess two long timbal ribs ( Fig. 8E ) as in Tibicinoides but have an uncus without a hook ( Fig. 8B ), the combination of which separates male Chlorocanta from other related genera. The uncus of Okanagana is not hooked ( Fig. 2B ) and all species have more than two long timbal ribs ( Fig. 2C ) including O. aurantiaca , the only other green Okanagana in North America. Tibicinoides have two long timbal ribs ( Fig. 3C ) but the uncus is always hooked ( Fig. 3B ). Hewlettia gen. nov. are green but have 5 apical cells in the hind wing ( Fig. 9A ) as opposed to 6 apical cells in Chlorocanta ( Fig. 8A ), features unique in both sexes of the genus Hewlettia gen. nov.

While the large size (up to 25 mm; Davis 1918; Hill & Marshall 2013), and green (or faded yellowish color) is enough to diagnose females with reliability, the shape of sternite VII ( Fig. 8D ) can ensure a diagnosis. The almost triangular primary notch with slight bulging to the lateral margins and distinct secondary notch lacks the consistent rounding of the notch seen in Tibicinoides ( Fig. 3D ) and there are no purely green (or yellowish) Okanagana of that size except for O. aurantiaca , which may be immediately diagnosed by the presence of a long, black longitudinal stripe on the abdomen.

Figures

FIGURE 2. Okanagana rimosa, type species of the genus Okanagana: A. dorsal habitus, B. male genitalia, right lateral view, C. timbal, D. female genitalia, ventral view, and E. female genitalia, right lateral view.

FIGURE 3. Tibicinoides cupreosparsa, type species of the genus Tibicinoides: A. dorsal habitus, B. male genitalia, right lateral view, C. timbal, D. female genitalia, ventral view, E. female genitalia, right lateral view.

FIGURE 8. Chlorocanta viridis. A. male habitus, dorsal view, B. male genitalia, right lateral view, C. male genitalia, dorsal view, D. female genitalia, ventral view, E. timbal.

FIGURE 9. Hewlettia nigriviridis. A. male habitus, dorsal view, B. female stridulatory ridge, C. female genitalia, ventral view, D. male genitalia, right lateral view, E. male genitalia, dorsal view, F. male sternite VIII, ventral view.