Neduba propsti Rentz & Weissman, 1981

Cole, Jeffrey A., Weissman, David B., Lightfoot, David C., Ueshima, Norihiro, Warchałowska-Śliwa, Elżbieta, Maryańska-Nadachowska, Anna & Chatfield-Taylor, Will, 2021, A revision of the shield-back katydid genus Neduba (Orthoptera: Tettigoniidae: Tettigoniinae: Nedubini), Zootaxa 4910 (1), pp. 1-92 : 46-49

Neduba propsti Rentz & Weissman, 1981

Fig. 19 (distribution), Fig. 20 (male and female habitus, calling song, drumming, male and female tremulation karyotype), Plate 2A (live habitus), Plate 4J (male calling song), Plate 7F (male ventral sclerite), Plate 10A (male titillators), Plate 11J (female subgenital plate).

Common name. Santa Catalina Island Shieldback.

History of recognition. Described as a Santa Catalina Island endemic ( Rentz & Weissman 1981). Listed under Aglaothorax in OSFO for unspecified reasons ( Cigliano et al. 2020).

Type material. The holotype male is in the CAS collection. Images of the holotype are available at OSFO ( Cigliano et al. 2020).

Measurements. (mm, ♁n = 9, ♀ n = 5) Hind femur ♁20.86–23.47, ♀ 24.10–25.89, pronotum total length ♁8.30– 9.45, ♀ 9.15–9.89, prozona length ♁4.15–5.55, ♀ 5.15–5.93, metazona dorsal length ♁3.90–4.90, ♀ 3.88– 4.15, pronotum constriction width ♁2.44–3.13, ♀ 2.98–3.22, metazona dorsal width ♁6.37–7.01, ♀ 6.27–7.22, head width ♁4.25–4.95, ♀ 5.18–5.54, ovipositor length ♀ 18.04–19.14.

Distribution. Restricted to Santa Catalina Island, Los Angeles County, California, USA. Probably found throughout the island in suitable habitat.

Habitat. Dense chaparral vegetation, often on steep hillsides and in canyon bottoms. Individuals prefer to sit on the inner twigs of tangles. Also, in gardens on non-native vegetation. One individual taken from ornamental eucalyptus (JAC, pers. obs.).

Seasonal occurrence. Adult records from mid-June (14-VI-1985, S Bennett, CAS) through July (28-VII-1981 DB Weissman, CAS) .

Stridulatory file. (n = 5) length 3.2–3.9 mm, 94–111 teeth, tooth density 30.4 ± 2.1 (28.2–33.0) teeth/mm.

Song. (n = 10) Continuous 200 ms MPTL at a brisk PTR of 4.4 ± 0.4 s- 1. PT consist of the least amount of pulses (toothstrikes) of any species (~20). PTF approaches the ultrasonic at 18.5 ± 3.5 kHz. A captive male drummed at irregular intervals while stridulating ( Fig. 20 ); the drums were audible and induced considerable substrate vibration in the cage.

Karyotype. (n = 4) Unique. 2n♁ = 24 (4m + 18t + XmYt). T85-12, S85-70, topotype.

Recognition. Shares the following morphological characters with N. lucubrata : a single apical spine on the fore tibiae, prosternal spines, and tegmina darkened apically. The stridulatory file has a lower tooth density (28–33 teeth/ mm) than any other species except those of the Castanea Group. Male genitalia of N. propsti are similar to those of N. castanea and N. macneilli , but the arms of the titillators of N. propsti have a shaft that is straight and not swollen at a distance of 1/6 from the base as in the latter two species ( Plate 10 ). The song is unique in having short MPTL produced continually at a rapid PTR. Females have the longest subgenital plate of any species, approximately 1.5 times longer than wide. This is the only nedubine on Santa Catalina Island ( Figs. 8 , 19 ) with the most southerly distribution of any Neduba .

Notes. N. propsti is an early branching lineage ( Figs. 3–5 ) that has apparently been isolated on Santa Catalina Island for a long time. The island has never been connected to mainland California ( Legg et al. 2004) being the product of tectonic uplift. Males may be wary and cease calling at the slightest disturbance, as much as a single leaf falling, and jump with little provocation (JAC pers. obs.). This is one of a handful of Neduba species that drum ( Weissman 2001; see also N. castanea , N. macneilli , and N. lucubrata below). Drumming was observed in captivity by a single male without a female present (JAC pers. obs) and not in the field; the context of drumming in the mating system is not known in this species.

Material examined. (n = 14) All USA, CA, Los Angeles Co.: 3♁, Hermit Gulch Campground , Avalon Canyon, Santa Catalina Island, 33.38265N, 118.33951W, 91 m, 9-10-VII-2013, JA Cole, LACM ; 1♁ same data except JAC; 2♀ , Santa Catalina Island , 33.383361N, 118.417576W, 1-VII-1983, DB Weissman, CAS; 1♀ , same data except 20-VII-1982, S Bennett, CAS; 1♀ , same data except 28-VII-1981, S Bennett, LACM ; 1♁, same data except 30-VI-1973, DB Weissman, CAS ; 4♁, Santa Catalina Island , Toyon Bay, 33.383N, 118.416W, 14-VI-1985, S Bennett, CAS; 1♀ , same data except 5-VII-1986, S Bennett, CAS .

Castanea Group

The Castanea Group is readily recognizable on account of the robust habitus, the short hind femora, by having only one spine on the anterior margin of the fore tibiae, and by the lack of prosternal spines. The lateral carinae of the male subgenital plate converge apically, although not as dramatically as in the Sierranus and Sequoia Groups , and the styli vary from articulate to rudimentary to absent. The posterior margins of the abdominal tergites have only slight crenulations. Superficially the species of this group resemble sympatric Aglaothorax ovata . Karyotypes also separate the two species in this group from all other Neduba . Castanea Group species occupy the dry slopes of central and southern California mountain ranges ( Fig. 8 ).

Figures

PLATE 2. Live habitus of the Propsti, Castanea, Lucubrata, and Sierranus Groups. A. N. propsti male, B. N. castanea topotype male, C. N. castanea female, D. N. macneilli male (photo credit James Bailey), E. N. lucubrata paratype male, F. N. sierranus female, G. N. sierranus male singing (note visible tegmina under pronotal shield).

FIGURE 3. Bayesian consensus tree showing species Groups (color coded) and species hypotheses. Nodes with <85% posterior probability are collapsed.

FIGURE 4. Comparison of A. rDNA, and B. mtDNA trees. Nodes with <85% posterior probability are collapsed. Species Groups are color coded.

FIGURE 5. rDNA Bayesian consensus tree. Nodes with <85% posterior probability are collapsed. Species Groups are color coded, and species hypotheses are indicated.

PLATE 4. Male calling songs of the Carinata and Propsti Groups.. A. N. carinata, B. N. oblongata, C. N. ambagiosa, D. N. diabolica, E. N. longiplutea, F. N. radicata, G. N. convexa, H. N. cascadia, I. N. steindachneri, J. N. propsti. Left column shows 4 s oscillogram windows, right column are 1 s windows.

PLATE 7. Ventral sclerites: Carinata, Propsti, Lucubrata, and Castanea Groups. A–C. N. convexa, D. N. steindachneri, E. N. cascadia, F. N. propsti, G–H. N. lucubrata, I. N. castanea, J–K. N. macneilli.

FIGURE 8. Distribution of Neduba species groups generated from records in this work.

PLATE 10. Titillator arms of Propsti (A), Castanea (B–C), Lucubrata (D), Sierranus (E–F), and Sequoia (G–I) Group species.

PLATE 11. Female subgenital plates of Carinata (A–I), Propsti (J), and Castanea (K–L) Group species.

FIGURE 19. Distribution of Propsti, Castanea, Lucubrata, Sierranus, and Sequoia Group species mapping records reported in this work.

FIGURE 20. N. propsti male and female habitus, calling song, male and female terminalia, karyotype.