Aglaothorax constrictans ( Rentz & Weissman, 1981 ), 2025

Aglaothorax constrictans ( Rentz & Weissman, 1981) View in CoL stat. rev.

Neduba (Aglaothorax) diminutiva constritcans — Rentz & Weissman, 1981: 92

Aglaothorax constrictans View in CoL stat. rev. (Revised to species level).

Fig. 28 View FIGURE 28 (distribution), Fig. 30 View FIGURE 30 (male and female habitus, calling song, male and female terminalia, karyotype), Plate 6 (male terminalia), Plate 9 (female subgenital plate), Plate 13 (male titillators), Plate 15 (male calling song).

Common name. Constricted Shieldback.

History of recognition. Described as a subspecies of Neduba (Aglaothorax) diminutiva from male material only ( Rentz & Weissman 1981). We elevate this taxon to species rank based on aberrant morphology for the Diminutiva Group in both males and females, and due to the appreciable genetic distance from other Diminutiva Group lineages.

Type material. The type series was collected from a dune area near the lighthouse at Bixby Ranch , Point Conception , Santa Barbara County, California. Images of the holotype and a paratype are available at OSFO ( Cigliano et al. 2025) . PARATYPES EXAMINED (n=13): USA, CA , Santa Barbara Co., Point Conception, Bixby Ranch , dunes nr. Lighthouse , 34.44860, -120.47155, 8-VI-1971, DC Rentz, DB Weissman, CAS, 1♂ GoogleMaps ; same data except 8-VII-1971, DC Rentz, DB Weissman, CAS, 1♂ GoogleMaps ; same data except 8-VIII-1974, DC Rentz, DB Weissman, CAS, 11♂ GoogleMaps .

Measurements. (mm, ♂ n=18, ♀ n=13) Hind femur ♂ 12.45–15.05, ♀ 14.70–18.37, pronotum total length ♂ 7.20–9.15, ♀ 7.16–9.50, prozona length ♂ 3.34–3.94, ♀ 1.34–4.76, metazona dorsal length ♂ 3.84–5.24, ♀ 3.35– 5.85, pronotum constriction width ♂ 2.40–5.47, ♀ 2.45–3.55, metazona dorsal width ♂ 5.15–6.51, ♀ 5.05–6.58, head width ♂ 3.40–3.95, ♀ 4.00–4.60, ovipositor length ♀ 10.55–11.79.

Distribution. South Coast Ranges of California bordering the Pacific Ocean. Distribution extends from Point Conception north through the Santa Lucia Range.

Habitat. Coastal dunes, coastal sage scrub, chaparral, and oak savanna from the beachfront to mountain slopes.

Seasonal occurrence. Adult activity spans late spring (4-VI-2006, JA Cole, LACM) through summer (8-IX-2002, JA Cole, LACM).

Stridulatory file. (n=16) length 3.00– 3.90 mm, 84–107 teeth, tooth density 28.7±2.3 (23.3–32.1) teeth/mm.

Song. (n=19) Common small Aglaothorax song with widely spaced, individually countable pulse trains. Length of pulse trains is 50±20 ms. Pulse trains repeat at a rate of 5.31± 0.69 s- 1. Mean peak frequency is 14.35±0.77 kHz. Long, variable echemes contain on average 38±19 (range 12–89) pulse trains. Silent intervals between echemes range from 7 to 29 s.

Karyotype. (n=4) 2n ♂ =24 (22t +XtYt), paratype T82-47 (S82-51).

Recognition. Typical for the Diminutiva Group, the male supra-anal plate is heart-shaped, expanded laterally and indented on the caudal margin, and the paraproct processes have an apical tooth. Otherwise, the morphology of this species is aberrant for the Diminutiva Group, the male titillators and female subgenital plate instead resembling those of the Morsei Group. Male titillator arms are short and barely curved as opposed to long and distinctly curved, the condition found in all other Diminutiva Group species. Females have short, triangular subgenital plate processes instead of long, digitiform processes as in the rest of the Diminutiva Group. For males, the apical position of the mesal tooth on the paraproct process excludes most Morsei Group species from consideration; A. amathitis , A. costalis , A. longipennis , and A. morsei all have a subapical tooth on the paraproct process along with a rounded supra-anal plate. The male titillator arms are notched at the base, a character state shared only with A. morsei . The female subgenital plate lateral processes are longer than wide unlike all Morsei Group females except A. kelainops .

Notes. This species is genetically a member of the Diminutiva Group ( Figs. 2–4 View FIGURE 2 View FIGURE 3 View FIGURE 4 ) but possesses morphology that is characteristic of the Morsei Group. Genetically, the closest relative is A. diminutiva which occurs in the South Coast Ranges to the east. Shared morphology may be the result of historical gene flow. Currently the ranges of A. constrictans and A. diminutiva are separated by the Salinas Valley. Other Morsei Group and Diminutiva Group lineages are found in the area where the Transverse and Peninsular Ranges meet in Ventura and Santa Barbara Counties, California, but we have not found any occurrences of sympatry. This species was, however, sympatric with both Neduba carinata Walker and N. lucubrata Cole, Weissman, & Lightfoot at Bottcher’s Gap in the Ventana Wilderness of the South Coast Ranges of California, this occurrence representing the highest count of sympatric nedubine species that we have encountered. The Nature Conservancy protected 25,000 acres of the Bixby Ranch type locality at Point Conception in 2017.

Material examined. (n=51) All USA, CA, Monterey Co., 0.9 miles E of Arroyo Seco and G17, intersection on Arroyo Seco , 36.25466, -121.43208, 192 m, 12-VIII-1982, DB Weissman, CAS GoogleMaps , 6♂, 4♀; Arroyo Seco Rd. , 0.6 mi. W of intersection with G6, 36.235139, -121.473392, 274 m, 29-VII-1983, DB Weissman, CAS GoogleMaps , 1♂, 1♀; Big Sur, SR1, 36.3547, -121.8136, 685 m, 20-VIII-2012, JA Cole, 1♂ sound recording; Bottcher’s Gap, Los Padres National Forest, 19 miles north of Big Sur off SR1 on Palo Colorado Road , 36.3550, -121.8138, 652 m, 20-21- VIII-2012, JA Cole, LACM GoogleMaps , 1♀; same data except JAC GoogleMaps , 1♀; Bottcher’s Gap, Los Padres National Forest, 19 miles north of Big Sur off SR1 on Palo Colorado Road , 36.3550, -121.8138, 652 m, 7-8-IX-2002, JA Cole, LACM GoogleMaps , 1♂; Palo Colorado Rd. , 3 mi. E of SR1, 36.3864, -121.8687, 327 m, 20-VIII-2012, JA Cole, LACM GoogleMaps , 5♂, 1♀, 2 pairs in copula; same data except JAC GoogleMaps , 1♂, 1♀; Pfeiffer Big Sur State Park , 36.248852, -121.782732, 5-VII-1986, DB & BI Weissman, CAS GoogleMaps , 1♂; Santa Barbara Co., Gaviota Pass Rest Area , 34.489433, -120.225984, 22 m, 14-VIII-1986, B Hebert, CSUN GoogleMaps , 1♀; Gaviota State Park , 34.47222, -120.22722, 4 m, 20-21-VIII-2013, JA Cole, AMNH GoogleMaps , 1♂; same data except LACM GoogleMaps , 8♂, 1♀; same data except JAC GoogleMaps , 3♂; Harris Grade Road, 5 miles north of Lompoc , 34.7238, -120.4368, 216 m, 3-VI-2006, JA Cole, JAC GoogleMaps , 1♂; same data except, 4-VI-2006, JA Cole, LACM GoogleMaps , 1♂; same data except JAC GoogleMaps , 1♀; junction Santa Rosa Rd. and US101 , 34.603319, -120.284877, 14-VII-1976, CAS GoogleMaps , 2♂; Santa Ynez Mountains , 0.8 mi. W Cold Arch Bridge on Hwy. 154, 34.528049, -119.843848, 320 m, DB Weissman, DC Lightfoot, CAS GoogleMaps , 1♂, 1♀; Vandenberg Air Force Base, 2.7 mi. NW of intersection 13th and Airfield on 13th, 34.764161, -120.579461, 90 m, 13-VIII-1982, DB Weissman, CAS GoogleMaps , 4♂, 1♀, CAS .