Aglaothorax armiger Rehn & Hebard, 1920

Aglaothorax armiger Rehn & Hebard, 1920 View in CoL comb. restored

Aglaothorax armiger View in CoL — Rehn & Hebard, 1920: 229.

Aglaothorax armiger View in CoL — Tinkham, 1944: 292.

Neduba (Aglaothorax) ovata armiger — Rentz & Birchim 1968: 83 (A change in status).

Aglaothorax armiger View in CoL comb. restored (Restored to species status as proposed by Rehn & Hebard, 1920).

Fig. 6 View FIGURE 6 (distribution), Fig. 11 View FIGURE 11 (male and female habitus, calling song, male and female terminalia, karyotype), Plate 4 View PLATE 4 (male terminalia), Plate 7 View PLATE 7 (female subgenital plate), Plate 10 (male titillators), Plate 14 (male calling song).

Common name. Armored Shieldback.

History of recognition. Described in Aglaothorax ( Rehn & Hebard 1920) . Correctly identified and associated with type material by Tinkham (1944). Transferred to Neduba (Aglaothorax) and relegated to a subspecies of N. (A.) ovata ( Rentz & Birchim 1968) . Transferred back to Aglaothorax ( Rentz & Colless 1990) where this species is currently classified as an A. ovatus subspecies ( Cigliano et al. 2025). We elevate A. armiger to species rank based on phylogenetic and morphological evidence, reinstating the taxonomic status of this species as originally described.

Type material. The holotype male deposited in ANSP is from Lee Canyon , Spring Mountains , Clark County, Nevada, taken from Joshua tree at 6000 feet elevation. Images of the holotype and allotype are available at OSFO ( Cigliano et al. 2025). TOPOTYPES EXAMINED: (n=29) USA, NV, Clark Co. , Charleston Peak, 36.272185, -115.695019, 15-VIII-1931, ER Tinkham, CAS, 1♂ GoogleMaps ; same data except 20-X-1939, ER Tinkham, CAS, 2♂ GoogleMaps ; Lee Canyon Road between mileposts 6 and 9, 36.399963, -115.567516, 15-VIII-1998, DB Weissman, DC Lightfoot, CAS, 1♂ GoogleMaps ; Lee Canyon Road , 36.399963, -115.567516, 1100-2200 m, 21-VII-1990, DB Weissman, DC Lightfoot, CAS, 3♂, 3♀ GoogleMaps ; Lee Canyon Road , 4 miles southwest of US95 , 36.43806, -115.51806, 1320 m, 8-VI-2023, JA Cole, AMNH, 1♂, 1♀ GoogleMaps ; same data except LACM 2♂, 2♀ GoogleMaps ; same data except JAC, 2♂, 2♀ GoogleMaps ; Lee Canyon Road , 5.2 miles southwest of US95 , 36.42624, -115.53464, 1426 m, 15-VI-2018, JA Cole, LACM, 1♂ GoogleMaps ; Lee Canyon , 36.399963, -115.567516, 1830 m, 2-VIII-1991, DB Weissman, DC Lightfoot, CAS, 1♂ GoogleMaps ; Lee Canyon , 36.399963, -115.567516, 6300-7500’ m, 30-VIII-1986, DB Weissman, DI Weissman, DCF Rentz, CAS, 5♂, 2♀ GoogleMaps .

Measurements. (mm, ♂ n=5, ♀ n=5) Hind femur ♂ 16.20–17.80, ♀ 19.10–20.37, pronotum total length ♂ 11.07– 12.80, ♀ 12.79–14.80, prozona length ♂ 4.51–5.80, ♀ 6.18–6.61, metazona dorsal length ♂ 6.56–7.00, ♀ 6.61–8.19, pronotum constriction width ♂ 3.40–3.90, ♀ 4.15–4.93, metazona dorsal width ♂ 7.24–8.05, ♀ 8.15–9.75, head width ♂ 5.22–6.00, ♀ 6.40–6.68, ovipositor length ♀ 17.65–20.47.

Distribution. Eastern Mojave Desert in Nevada. The type locality is along the eastern slope of the Charleston Mountains, Clark County.

Habitat. Joshua Tree and pinyon-juniper woodlands. The description states that occurrence at the type locality was restricted to Joshua tree woodland, where they were found 4–8 feet above the ground, and found most often at 5–6 feet hiding in the dry leaves at the base of green leaves ( Rehn & Hebard 1920). Topotype specimens were later taken from juniper and mixed conifer woodlands ( Tinkham 1944). We found them on Joshua Trees and yucca at night, sometimes 4 m above the ground.

Seasonal occurrence. Summer (8-VI-2023, JA Cole, LACM) through Fall (20-X-1939, ER Tinkham, CAS), maturing earlier at lower elevations. Nymphs alongside adults in late spring (8-VI-2023, JA Cole, LACM), with one female observed eclosing that night .

Stridulatory file. (n=5) length 3.90–4.80 mm, 94–106 teeth, tooth density 23.1±1.4 (20.8–24.1) teeth/mm.

Song. (n=7) Sporadic song that consists of single pulse trains or brief echemes. Pulse trains 50 ms in length are repeated at a rate of 10.26± 0.97 s- 1. Mean peak frequency is 11.58±0.83 kHz. Males may produce pulse trains alone or group them into echemes containing 1–4 (mean 3±1) pulse trains. Isolated pulse trains are more likely to occur at the onset of singing or after a male is disturbed. Silent intervals between echemes last 1–6 (mean 2.16±1.70) s. The original description mentions intermittent sound production during an afternoon ( Rehn & Hebard 1920).

Karyotype. (n=5) 2n ♂ =23(22t +Xt), S86-104, T86-98, topotype.

Recognition. Morphology, coloration, geography. Ground color is generally tan or yellow, unlike the rich green that is common in other Ovatus Group species or the wood-brown coloration of A. gurneyi . The abdominal dorsum has a reddish stripe and the tegmina are white, unlike the wood-brown unstriped abdomen and brown tegmina of A. gurneyi . The male supra-anal plate of A. armiger is wider than long in contrast to A. giganteus , A. khioneos , A. ovatus , and A. tinkhamorum , which have supra-anal plates that are as long as wide. From 16 to 18 mm long, the hind femora appear shorter than those of A. giganteus , A. ovatus , and A. tinkhamorum . The male paraproct process is about twice as long as wide, cylindrical, and with a subapical ventrally directed heavy triangular tooth, unlike the apical tooth on the slenderer processes of A. segnis and A. strobilion . Black markings are generally reduced on the pronotal disk to a central pair of black spots and perhaps limited black streaking, a coloration otherwise approached only by A. tinkhamorum .

Notes. The type locality of A. armiger, Lee Canyon , is a sky island in the eastern Mojave Desert that is known for its endemism, and as a biodiversity hotspot for Orthoptera in particular ( Rentz 1972). A. armiger populations are distributed to the east of Mount Charleston in the rain shadow. White Mountains, California populations classified as this species ( Rentz & Birchim 1968) are here described as new (see A. khioneos species account below).

Material examined. (n=4) All USA, NV , Clark Co., Willow Creek , 36.576070, -115.732522, 1820 m, 16-VI-1985, JB Knight, NDAC, 2♂ GoogleMaps ; Mineral Co., Cottonwood Creek , 38.648524, -118.762961, 2286 m, 9-VIII-1990, RC Bechtel, JB Knight, SD Cichowlaz, NDAC, 2♂ GoogleMaps .