Aglaothorax strobilion Cole, Weissman, and Lightfoot, 2025

Cole, Jeffrey A., Weissman, David B., Lightfoot, David C., Ueshima, Norihiro & Warchałowska-Śliwa, Elżbieta, 2025, A revision of the shield-backed katydid genus Aglaothorax (Orthoptera: Tettigoniidae: Tettigoniinae: Nedubini), Zootaxa 5667 (1), pp. 1-104 : 32-34

Aglaothorax strobilion Cole, Weissman, and Lightfoot , sp. nov.

Fig. 6 (distribution), Fig. 12 (male and female habitus, calling song, male and female terminalia, karyotype), Plate 4 (male terminalia), Plate 7 (female subgenital plate), Plate 10 (male titillators), Plate 14 (male calling song)

Common name. Currant Shieldback.

History of recognition. Noted as intergrades between armiger and segnis with small body size ( Rentz & Birchim 1968). We describe this population as a new species based on cytogenetic, morphological, and phylogenetic evidence, and also the remote, isolated geography.

Type material. HOLOTYPE MALE: USA, NV, Nye Co., Currant Summit , 38.82081, -115.33528, 1950 m, 19-VIII-2009, DB Weissman, DC Lightfoot, CAS S09-140 , R09-211 , D36 , T09-7 , SING0371 , deposited at CAS, Entomology type #20383 . PARATYPES (n=8) USA, NV, Nye Co., 9.9 M E Currant on Hwy. 6, 38.742013, - 115.290742, 2042 m, 29-VIII-1986, DB Weissman, BI Weissman , DCF Rentz , CAS, 6♂; same data as holotype , CAS, 2♂ .

Measurements. (mm, ♂ n=5) Hind femur ♂ 14.86–17.58, pronotum total length ♂ 9.85–11.73, prozona length ♂ 4.26–5.13, metazona dorsal length ♂ 5.59–6.60, pronotum constriction width ♂ 3.37–3.75, metazona dorsal width ♂ 6.80–7.62, head width ♂ 5.06–5.62.

Distribution. Limited records are from the Currant Mountain Wilderness in the White Pine Range, Humboldt- Toiyabe National Forest, Nevada.

Habitat. Pinyon-juniper woodland at high elevations, from 1950–2050 m. Sings from high in junipers.

Seasonal occurrence. Limited records suggest late summer adult activity (19-VIII-2009, DB Weissman & DC Lightfoot, CAS to 29-VIII-1986, DB Weissman, BI Weissman, DCF Rentz, CAS). Adult activity late in the season corresponds with high elevation habitat.

Stridulatory file. (n=5) length 3.90–4.15 mm, 85–107 teeth, tooth density 24.5±2.3 (20.7–26.6) teeth/mm.

Song. (n=2) Pulse trains 50±10 ms in length are repeated at a rate of 9.65± 0.57 s- 1. Mean peak frequency is 11.45±1.71 kHz. Echemes group 2–4 (mean 3±1) pulse trains with 0.93–1.77 (mean 1.35±0.60) s of silence between echemes.

Karyotype. (n=5) 2n ♂ =23 (22t +Xt), S86-103, T86-101, paratype.

Recognition. Morphology, karyotype. Small body size for Ovatus Group, pronotum length 10–12 mm. Similar in habitus to A. segnis but smaller. Like A. segnis and unlike all other Ovata Group species, including A. armiger , paraproct process with apical, mesally directed tooth. Paraproct processes shorter in A. strobilion , about 2 times as long as wide, than A. segnis in which those processes are about 3 times as long as wide. Pronotal disk with abundant black longitudinal streaks unlike A. armiger , which has reduced black streaking on pronotal disk. Karyotype 2n ♂ =23, typical for Ovatus Group but unlike 2n ♂ =24 A. segn is. Female unknown.

Etymology. Gr. strobilion a small pinecone. Refers to the small body size and pinyon-juniper habitat preference.

Notes. This population highlights the need for additional fieldwork in the mountains of the Nevada Basin and Range province, where endemics may yet be found on remote mountain island habitats. The impetus to delve further into this population came from its classification as an intergrade ( Rentz & Birchim 1968). Karyotyping showed that this population ( Fig. 12 ) did not have the same chromosome complement as A. segnis ( Fig. 10 ). The concatenated phylogenetic hypothesis found this population more closely related to A. armiger ( Fig. 4 ), with which it shares the typical 2n ♂ =23 karyotype, than with the karyotypically divergent A. segnis . The type locality of A. strobilion is separated from that of A. segnis by about 150 km and from that of A. armiger by approximately 280 km ( Fig. 6 ). A distinct constellation of characters, together with its geographic isolation, prompted specific distinction.

Material examined. See Type Material above.

Figures

PLATE 4. Male terminalia of Ovatus Group, dorsal view.

FIGURE 4. Bayesian consensus tree of concatenated matrix. Terminals in red show exemplars involved in mitochondrial capture.

FIGURE 6. Distribution of Ovatus Group species.

PLATE 7. Female subgenital plates of Ovatus Group, ventral view.

FIGURE 10. A. segnis male and female habitus, calling song, male and female terminalia, and karyotype. Idiogram top panel shows karyotype 2n♂=24; B. Plate showing all 24 chromosomes; C. Metaphase I, showing 11 autosomal pairs and associated XY pair.

FIGURE 12. A. strobilion male habitus, calling song, terminalia, and karyotype.