Tibicinoides Distant, 1914

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 : 514-516

Tibicinoides Distant, 1914

Fig. 2 (A. dorsal habitus, B. male genitalia, right lateral view, C. timbal, D. female genitalia, ventral view, E. female genitalia, right lateral view)

Type species: Tibicen cupreo-sparsa Uhler, 1889

Included species: boweni ( Chatfield-Taylor & Cole, 2020) comb. n., catalina ( Davis, 1936) comb. n., cupreosparsa ( Uhler, 1889) , hesperia ( Uhler, 1876) comb. n., mercedita ( Davis, 1915) , minuta ( Davis, 1915) , pallidula ( Davis, 1917a) comb. n., pernix ( Bliven, 1964) comb. n., rubrovenosa ( Davis, 1915) comb. n., simulata ( Davis, 1921) comb. n., striatipes ( Haldeman, 1852) comb. n., uncinata ( Van Duzee, 1915) comb. n., utahensis ( Davis, 1919) comb. n., vanduzeei ( Distant, 1914) comb. n.

Etymology: Unknown. Perhaps referencing gestalt similarity (g. -oides “likeness”) with Tibicen , meaning “flute player,” a genus established early in cicada systematic history in which the type species was originally described, and in which several other early species were at one time or another classified. Perhaps also refers to similarity with the related European genus Tibicina . Neuter.

Distribution: Tibicinoides are found in western North America. Their range extends north to Washington state, south into southern Baja California, México, and east into Kansas following shortgrass and sage dominated prairie ( Sanborn & Phillips 2013).

Redescription: Body size is highly variable with both inter and intra-specific variation. Head: The width of the head and eyes is equal to subequal that of the apical pronotal margin. The clypeus is variably pronounced. The center of the vertex has a deeply sulcate epicranial suture. Thorax: The pronotal margins are subquadrate to apically constricted with a longitudinal sulcus of varying depth running down the center. Two bilateral fissures run inwards towards the center of the pronotum at an anterior-posterior angle. The humeral and apical angles of the pronotum are distinct or not. The cruciform elevation is located directly anterior to the hind margin of the mesonotum. The anterior lateral sides of the mesonotum show vestigial stridulatory grooves in both sexes. The metanotum is clearly visible. Most species have the head, pronotum, and mesonotum variably black, brown, and yellow, but with a distinct set of four markings arranged in a trapezoid directly anterior to the cruciform elevation. Wings: Both fore and hind wings are hyaline, and the basal membranes are variable in color but typically orange. The fore wing length is 2.4–2.9 times the width, with 8 apical cells. The trapezoidal-shaped radial cell reaches the costal node situated halfway along the length of the costa. The ratio of apical cell to ulnar cell length is subequal in most species but 2: 1 in the species of Tibicinoides prior to its revision. The hind wing has 6 apical cells with a typical branched cubitus anterior (CuA) vein ( Fig. 3A ). The wing venation color is variable both within and among species with the base of the wings strongly infuscated or not. Legs: Metacoxa with a meracanthus with a distinct triangular shape, typically as long or longer than the coxa. All tibiae are often heavily setose but only the metatibiae have spines. Abdomen: In males the timbals are completely exposed with the timbal membrane having two long and two short ribs ( Fig. 3C ). The majority of female Tibicinoides show a distinct vertical gap between tergite VII and tergite VIII, giving them a hump-backed appearance ( Fig. 3E ), and epipleurite VII is usually subequal in length to epipleurite VI. Tergite VII is angled slightly inward posteriorly, particularly towards the base, causing this appearance. The abdominal sternites can be heavily setose or not, with intra-specific variation in this regard.

Male Genitalia: Sternite VII in males is variably shaped, covering base of sternite VIII. Sternite VIII extends parallel to the length of the body, partially housing the uncus and aedeagus. The uncus is generally straight in the lateral aspect and curves at the tip, forming the characteristic hook of the genus ( Fig. 3B ). The aedeagus is variable but is often a species-specific shape and is attached to the ventral surface of the uncus.

Female Genitalia: Sternite VII is variably excavated on its posterior margin, forming a primary notch with a secondary notch in the center of the primary ( Fig. 3D ). Both excavations are rounded in their entirety, forming no distinct angles between the primary and secondary notch (if clear). The sides of sternite VII form rounded apical prongs that vary in shape. Both traits are often species-specific.

Diagnosis: Tibicinoides and Okanagana are North American cicadas 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. Diagnosing Tibicinoides from other North American cicadas is simple with males but more difficult with females. Males can be differentiated by the combination of an uncus with a distinct hook ( Fig. 3B ) and exposed timbals with two long and two short timbal ribs ( Fig 3C ).

Diagnosing females from Okanagana by morphology alone is difficult. Phenotypically they are not sexually dimorphic from males making field identification easier if both sexes are present. The hump-backed look of female Tibicinoides ( Fig. 3E ) is seen only rarely in Okanagana , which appear much more streamlined in the lateral aspect ( Fig. 2E ), and this is the most useful feature for in-field diagnosis. This appearance is caused by a distinct vertical gap between tergites VII and VIII with tergite VII being angled inward towards the base. The result is that epipleurite VII is subequal in length to epipleurite VI, and angles inward at a sharper angle relative to epipleurite VI. Okanagana lack the inward constriction of tergite VII, causing epipleurite VII to be distinctly longer than epipleurite VI, without a clear difference in angle. Rough handling of the specimen can distort this feature. The primary and secondary notches of sternite VII are both completely rounded with no distinct angles, eliminating the majority of Okanagana which often have distinct angles in the primary notch or have the primary or secondary notches V-shaped. However, the best way to identify female Tibicinoides is by gestalt, and it becomes easier with more experience. Many species of Tibicinoides also have at least a single distinct feature identifying them to the genus.

This paper describes two additional genera; Chlorocanta gen. nov. and Hewlettia gen. nov. Males of these two genera can be diagnosed from all Tibicinoides by a lack of a hooked uncus ( Figs. 8B , 9B ). Female Chlorocanta gen. nov. can be diagnosed from Tibicinoides by their green color (yellow when faded) and the almost triangular primary notch with slight bulging to the lateral margins and distinct secondary notch ( Fig. 8D ), which lacks the consistent rounding of the notch seen in Tibicinoides . Hewlettia gen. nov. females are distinguishable entirely by the green and black patterning across the body and the presence of 5 rather than 6 apical cells on the hind wing ( Fig. 9A ).

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.