From: Cole et al. 2025.
The following key works best with series of specimens, and representatives of both sexes are required to navigate much of the key. Morphological diagnosis is based on constellations of characters. Single characters are rarely diagnostic because identical or similar character states may occur across several species. The morphological characters incorporated into the key are typical or average but may not cover the range of variation within species. (From Cole at al. 2025)
Title, introductory, and key was taken directly from Cole et al. 2025.
| 1a | Large body size, pronotum length >10 mm in males and >11 mm in females, female ovipositor length >16 mm. Green forms common (Plate 1; Ovatus Group). | 2 |
| 1b | Small body size, male pronotum length <10 mm in males and females, female ovipositor length < 16 mm. Diverse color patterns but no green forms (Plates 2-3). | 9 |
| 2a | Body coloration wood brown. Abdomen without a central longitudinal red-brown stripe (Fig. 14, Plate 1). Male tegmina brown. Male prozona rugose, metazona with shallow oblique depressions and irregular fine rugae (Fig. 14). Male paraproct processes long, about 3 times as long as wide, dorsoventrally flattened, and with a subapical ventrally oriented tooth (as in Fig. 5-3b.1, Fig. 14). Female subgenital plate lateral processes of medium length, thick at base, tapering to a sharp point (Fig. 14, Plate 7). Inhabits high elevation woodlands of the San Gabriel and San Bernardino Mountains of Southern California (Fig. 6). | gurneyi |
| 2b | Body coloration variable but not wood brown. Abdomen with a central longitudinal red-brown stripe (Plate 1). Male tegmina ivory white. Male prozona variable, metazona smooth with only fine transverse grooves and punctate around apical 1/4 of periphery. Female subgenital plate variable. | 3 |
| 3a | Male paraproct processes with mesally directed apical tooth (Fig. 5-3a.1). Female subgenital plate processes short, thick, tapering to a blunt point (Fig. 5-3a.2; female of A. strobilion unknown). Inhabits pinyon-juniper woodlands in mountain ranges of eastern Nevada. | 4 |
| 3b | Male paraproct tooth positioned subapically and ventrally (Fig. 5-3b.1). Female subgenital plate processes variable. | 5 |
| 4a | Male paraproct processes long, thin, slender, about 3 times as long as wide (as in Fig. 5-3a.1, Fig. 10, Plate 4). Male pronotum constriction width narrow relative to metazona width (measured as in Fig. 5-4), ratio 2.24-2.47. Karyotype 2n♂=24 (Fig. 10). Mountain ranges of southeastern Nevada (Fig. 6). | segnis |
| 4b | Male paraproct processes slender but shorter than above, about 2 times as long as wide (Fig. 12, Plate 4). Male pronotum constriction width broad relative to metazona width, ratio 1.97-2.20. Typical Ovata Group karyotype of 2n♂=23. Mountain ranges of east central Nevada (Fig. 6). | strobilion |
| 5a | Male pronotum distinctly rugose on prozona in addition to a posteromesally trending oblique groove or row of punctations on each side (as in Fig. 5-6a.1, 6b.1). Female subgenital plate processes long, slender, acuminate (as in Fig. 5-6a.2). | 6 |
| 5b | Male prozona with few rugae in addition to the posteromesally trending groove or row of punctations on each side. Female subgenital plate variable. | 7 |
| 6a | Male pronotum heavily and irregularly rugose on prozona (Figs. 5-6a.1, Fig. 8), metazona rises steeply above transverse sulcus. Pronotum with black coloration consisting of longitudinal streaks of varying intensity in center of disk in addition spots or bars around periphery of disk (Figs. 5-6a.1, Fig. 8). Male titillator arms stout, smoothly curved laterally (Fig. 8, Plate 10). Eastern slopes of Sierra Nevada, California, at moderate to high elevations (Fig. 6). | giganteus |
| 6b | Male pronotum less rugose on prozona, rugae wart-like, transition to metazona at transverse sulcus not abrupt, both surfaces on similar planes (Fig. 5-6b.1). Pronotal disk rich yellow-green in life, black coloration reduced to a single central spot and irregular heavy black bars around periphery of disk. Male titillator arms long, slender, bowed laterally (Fig. 9, Plate 10). Distributed along the mountains bordering the Colorado Desert, California (Fig. 6). | tinkhamorum |
| 7a | Male supra-anal plate wider than long (measured as in Fig. 5-7). Body ground color typically tan or light brown. Pronotum often with reduced coloration on center of disk, black markings commonly restricted to bars around the periphery of disk and a central pair of spots (Fig. 11, Plate 1). Female subgenital plate processes stout and of moderate length (as in Fig. 5-3a.2, Fig. 11, Plate 7). Mountains of southwestern Nevada (Fig. 6). | armiger |
| 7b | Male supra-anal plate as wide as long. Pronotum usually with more extensive coloration on disk. Female subgenital plate variable. Mountains of California. | 8 |
| 8a | Pronotum usually with wide white longitudinal stripes, and often fine brown streaks, on disk in addition to black streaks and central black spot (Fig. 7, Plate 1). Female subgenital plate lateral processes long, slender, acuminate (as in Fig. 5-6a.2, Fig. 7, Plate 7). Mountains surrounding and within California Mojave Desert (Fig. 6). | ovatus |
| 8b | Pronotum with heavy black longitudinal streaks on disk but without white and/or brown streaks (Fig. 13, Plate 1). Female subgenital plate lateral processes stout and of moderate length (as in Fig. 5-3a.2, Fig. 13, Plate 7). High elevation pinyon-juniper of White Mountains and Inyo Mountains of eastern California (Fig. 6). | khioneos |
| 9a | Male supra-anal plate heart-shaped, expanded and bilobed caudally, or at least with caudal margin indented (Fig. 5-9a.1). Male paraproct processes with apical tooth. Female subgenital plate (except A. constrictans) processes long, digitiform (Fig. 5-9a.2; Diminutiva Group). | 10 |
| 9b | Male supra-anal plate rounded and tongue-like (e.g. Fig. 5-9b.1) or square with rounded edges, dorsally flat to concave. Male paraproct processes with tooth position variable but commonly subapical (Fig. 5-9b.1). Female subgenital plate processes short triangular projections (Fig. 5-9b.2; Morsei Group). | 15 |
| 10a | Male paraproct processes short, blunt, as long as wide (Fig. 5-10a.1, Fig. 30, Plate 6). Male titillator arms short, barely curved, with distinct mesal notch at base (Fig. 5-10a.2, Fig. 30, Plate 13). Female subgenital plate processes short, triangular, barely longer than wide (as in Fig. 5-9b.2). South Coast Ranges of California (Fig. 27). | constrictans |
| 10b | Male paraproct processes long, thin, cylindrical, much longer than wide (Fig. 5-10b.1). Male titillator arms long, curved, not notched (Fig. 5-10b.2) but may be slightly constricted at base. Female subgenital plate processes long, digitiform (as in Fig. 5-9a.2). | 11 |
| 11a | Male titillator arms long, thin, and strongly bowed laterally at 1/2 length (Fig. 5-10b.2, Fig. 31, Plate 13). Female subgenital plate lateral processes long, thin, sharply pointed (Fig. 5-9a.2, Fig. 31, Plate 9). Santa Monica Mountains of California (Fig. 27). | dactyla |
| 11b | Male titillator arms shorter than above and smoothy curved. Female subgenital plate processes shorter, broader at base, tapering to a blunt apex (as in Fig. 5-12a, -12b). | 12 |
| 12a | Female subgenital plate lateral processes join caudal margin of plate at a right angle (Fig. 5-12a, Fig. 29, Plate 9). Ventral surface of plate flat anterior to caudal margin (Fig. 5-12a, Fig. 29, Plate 9). Karyotype unique among Diminutiva and Morsei Groups, 2n♂=23. Distributed in South Coast Ranges of California. | diminutiva |
| 12b | Female subgenital plate lateral processes round onto caudal margin (Fig. 5-12b). Ventral surface of plate concave anterior to caudal margin (Fig. 5-12b). Typical small Aglaothorax karyotype 2n♂=24. | 13 |
| 13a | Large body size for Diminutiva Group, male hind femur length >15 mm, pronotum length >9 mm. Male titillator arms slightly narrowed at base around entire circumference and barely curved (Fig. 5-13a, Fig. 33, Plate 13). Mountains of Ventura County, California. | oreibates |
| 13b | Small body size, male hind femur length <14 mm, pronotum length <9 mm. Male titillator arms broad at base, tapered and smoothly curved (Fig. 5-13b) | 14 |
| 14a | Santa Ynez Mountains of Santa Barbara County, California (Fig. 27). | poecilonotum |
| 14b | Transverse Ranges of California including Tehachapi Mountains (Fig. 27). | acrolophitus |
| 15a | Male paraproct process long, narrow, and cylindrical, more than 2 times longer than wide (as in Fig. 5-10b.1). | 16 |
| 15b | Male paraproct process 2 times longer than wide or shorter (as in Fig. 5-9b.1, 5-10a.1). | 18 |
| 16a | Prosternal spines conical in both sexes (Fig. 5-16a). Male supra-anal plate concave, rounded or square with laterocaudal corners rounded (Fig. 27, Plate 8). Karyotype 2n♂=22. distributed in Baja California, Mexico (Fig. 15). | sphenosternum |
| 16b | Prosternal spines long, thin, spinelike in both sexes (Fig. 5-16b). Male supra-anal plate flat. Karyotype 2n♂=24. | 17 |
| 17a | Male subgenital plate with thick, conical styli (Fig 5-17a, Fig. 23). Male supra-anal plate rounded, tongue-like (as in Fig. 9b.1, Fig. 23, Plate 5). Male titillators of moderate length and distinctly bowed at 1/2 to 2/3 length from base (Fig. 23, Plate 12). Transverse Ranges and adjacent basins (Fig. 15). | conistylus |
| 17b | Male subgenital plate with typical thin, cylindrical, straight to slightly curved styli (Fig. 5-17b). Male supra-anal plate square with laterocaudal corners rounded (Fig. 24, Plate 5). Male titillator arms short, nearly straight, barely curved laterally in apical 1/3 (Fig. 24, Plate 12). Peninsular Ranges of California (Fig. 15). | nesiazo |
| 18a | Male paraproct with mesal tooth apical (as in Fig. 5-9a.1). | 19 |
| 18b | Male paraproct with mesal tooth subapical (as in Fig. 5-9b.1) | 20 |
| 19a | Male titillator arms short, nearly straight, barely curved laterally in apical 1/3 (Fig. 5-19a.1, Fig. 26, Plate 12). Male stridulatory file tooth density 25-27 teeth/mm. Karyotype 2n♂=20 (Fig. 26). Female subgenital plate processes longer than wide (Fig. 5-19a.2, Fig. 26, Plate 8). Baja California, Mexico (Fig. 15). | kelainops |
| 19b | Male titillator arms smoothly curved (Fig. 5-19b.1, Fig. 25, Plate 12). Male stridulatory file tooth density 27-33 teeth/mm. Karyotype 2n♂=24 (Fig. 25). Female subgenital plate processes as long as wide (Fig. 5-19b.2, Fig. 25, Plate 8). Baja California, Mexico (Fig. 15). | bufonoides |
| 20a | Male supra-anal plate concave dorsally (as in Fig. 5-20a). Male song with rapidly produced pulse trains that are grouped into echemes (“chirps”) (Figs. 17, 19, Plate 14). | 21 |
| 20b | Male supra-anal plate flat dorsally (as in Fig. 5-20b). Male song variable but usually (except A. amathitis (Fig. 20, Plate 14) with slowly produced pulse trains that are not generally organized into echemes) (Figs. 16, 21-23). | 22 |
| 21a | Male paraproct processes short, thick, knob-like, as long as wide (Fig. 5-20a, Figs. 17, 18, Plate 5). Female subgenital plate without projection or tooth between short, triangular lateral processes (Fig. 5-21a). Song with long echemes, the syllables of which occur too rapidly to be counted by a human listener (Fig. 17, Plate 14). Found in Santa Monica Mountains west of Malibu Creek, California (Fig. 15). | costalis |
| 21b | Male paraproct processes about 2 times as long as wide (Fig. 19, Plate 5). Female subgenital plate with a low to pronounced rounded to triangular projection between short, triangular lateral processes (as in Fig. 5-21b, Fig. 19, Plate 8). Song with short echemes that consist of 4 ± 2 pulse trains that may occur slow enough to be counted at ambient temperature (Fig. 19, Plate 14). Found in Santa Monica Mountains east of Malibu Creek, California (Fig. 15). | longipennis |
| 22a | Subapical tooth on male paraproct process located far basal from apex. | 23 |
| 22b | Subapical tooth on male paraproct process located close to apex. | 24 |
| 23a | Male titillator arms of moderate length, evenly curved (Fig. 5-22a, Fig. 21, Plate 12). Found on northern chain of California Channel Islands (Fig. 15). | islandica |
| 23b | Male titillator arms short, nearly straight, barely curved laterally (Fig. 5-22b, Fig. 22, Plate 12). Found on mainland, at moderate to high elevations in the San Bernardino Mountains and San Jacinto Mountains of California (Fig. 15). | hulodomus |
| 24a | Male titillator arms constricted at base (Fig. 5-24a, Fig. 16, Plate 11). Calling song with pulse trains produced slowly in irregular echemes (Fig. 16, Plate 14). San Gabriel Mountains, California (Fig. 15). | morsei |
| 24b | Male titillator arms not constricted at base (Fig. 5-24b, Fig. 20, Plate 11). Calling song with rapidly produced echemes (Fig. 20, Plate 14). Distributed on relict sand dunes and coastal bluffs of Los Angeles Basin and Palos Verdes Peninsula, California (Fig. 15). | amathitis |