Neduba lucubrata Cole, Weissman, & Lightfoot, 2021

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 : 55-57

Neduba lucubrata Cole, Weissman, & Lightfoot , sp. n.

Fig. 19 (distribution), Fig. 23 (male and female habitus, calling song, drumming, male and female terminalia, karyotype), Plate 2E (live habitus), Plate 5C (male calling song), Plate 7 G–H (male ventral sclerites), Plate 10D (male titillators), Plate 12A (female subgenital plate).

Common name. Midnight Shieldback.

History of recognition. None.

Type material. HOLOTYPE MALE, USA, CA, Monterey Co., Miller’s Lodge , 0.6 miles west jct. Arroyo Seco Road and G16, 36.25466N, 121.43208W, 192 m, 22-VII-2015, JA Cole, DB Weissman, JAC000002197 [specimen barcode], DNA161 [tissue], SING0503 [DNA extraction], JCT15-08 [karyotope], genitalia in vial under specimen, deposited in CAS, Entomology type #19712.

PARATYPES (n = 32): All USA, CA , Monterey Co., 4♁, 1♀, same data as holotype, LACM ; 2♁, 1♀, Arroyo Seco Rd. , 0.6 mi. W of intersection with G16, 36.235139N, 121.473392W, 274 m, 29-VII-1983, DB Weissman, CAS ; 3♁, Bottcher’s Gap, Los Padres National Forest, 19 miles north of Big Sur off SR1 on Palo Colorado Road , 36.355N, 121.8138W, 652 m, 20-21-VIII-2012, JA Cole, LACM ; 1♁, same data except 7-8-IX-2002, JA Cole, LACM ; 7♁, Nacimiento-Ferguson Rd., at bridge of Nacimiento River , 8.4 miles east of SR1, 36.0135N, 121.4216W, 587 m, 19-20-VIII-2012, JA Cole, LACM ; San Benito Co., 9♁, Short Fence Trailhead, Coalinga Road , Laguna Mountain Recreation Area , BLM, 36.36403N, 120.8784W, 670 m, 10-11-VIII-2017, JA Cole, LACM ; 2♁, same data except 10-11-VIII-2017, JA Cole, JAC ; 2♁, Upper Sweetwater Campground, Coalinga Road, Laguna Mountain Recreation Area , BLM, 36.36067N, 120.85256W, 848 m, 10-11-VIII-2017, JA Cole, LACM .

Measurements. (mm, ♁n = 24, ♀ n = 2) Hind femur ♁16.35–20.74, ♀ 21.61–22.90, pronotum total length ♁7.04–9.03, ♀ 8.95–9.17, prozona length ♁2.65–4.78, ♀ 4.02–4.18, metazona dorsal length ♁3.85–5.10, ♀ 4.77– 5.15, pronotum constriction width ♁1.85–2.66, ♀ 2.70–3.35, metazona dorsal width ♁5.36–6.25, ♀ 5.76–6.35, head width ♁3.90–4.70, ♀ 5.11–5.46, ovipositor length ♀ 16.50–16.60.

Distribution. Santa Lucia and Diablo Ranges in the South Coast Range, California.

Habitat. Mixed woodland and chaparral. Taken from twigs in tangles, poison oak, and California sage ( Artemisia californica Less. ). Males call approximately 1 m above ground level in thick tangles. At dusk two males and one female emerged for nocturnal activity from a pack rat nest, suggesting that this structure served as a daytime shelter for an aggregation of individuals. These individuals retreated into the nest when disturbed.

Seasonal occurrence. Adults from late July (22-VII-2015, JA Cole and DB Weissman, LACM) through early September (8-IX-2002, JA Cole, LACM).

Stridulatory file. (n = 7) length 3.2–3.8 mm, 121–186 teeth, tooth density 45.9 ± 4.2 (38.4–50.0) teeth/mm.

Song. (n = 31) Brief bouts separated by long intervals between bouts. PTR is 4.0 ± 0.5 s- 1. Males may add one PT to each successive bout, for example three successive bouts may consist of 3 PT, 4 PT, then 5 PT, and then the cycle recommences at 3 PT. PTF is 14.9 ± 0.8 kHz. Males may accompany stridulation with audible drumming, which is generated by the abdomen striking the substrate ( Weissman 2001; JAC pers. obs.). Drumming coincides with partial PT at the beginning of a bout ( Fig. 23 ). Drumming does not occur frequently and may not occur in all populations. Drumming was observed at the Monterey County localities of Arroyo Seco (one of two males, DBW, JAC, pers. obs.) and Bottcher’s Gap ( JAC, pers. obs.), but not at any San Benito County localities .

Karyotype. (n = 8) Unique. 2n♁ = 24 (2m + 20t + XtYt). T83-37, S83-107, paratopotype.

Recognition. With a single apical protibial spine, dark apical tegminal spots and prosternal spines, this species may be confused only with N. propsti , a larger species that does not occur on the California mainland. The female subgenital plate length and width are subequal, in contrast with the elongated subgenital plate of N. propsti . The song, which consists of short stridulation bouts accompanied by drumming, is unique.

Etymology. l. lucubrata burning the midnight oil, descriptive of male acoustic activity continuing throughout the night.

Notes. This species shares morphological and genitalic characteristics with N. propsti as well as with the species of the Sierranus and Castanea Groups. Santa Lucia Range and Diablo Range populations are genetically distinct ( Figs. 3–5 ) but are separable neither morphologically nor bioacoustically. The chirping song structure combined with abdominal drumming makes N. lucubrata the most acoustically distinct species of Neduba . Selection for mate recognition may have driven the evolution of distinctive song phrasing in N. lucubrata , as within its distribution are found two sympatric nedubines: N. carinata and a small Aglaothorax species. Females may require silent periods of an appropriate intermediate length between bouts to recognize a conspecific male signal (Cole 2016): intermediate length gaps between PT bouts will contrast with the continuous PT production of sympatric N. carinata as well and the long periods of silence between pulse production in Aglaothorax .

Material examined. Type series only. See Type material above.

Sierranus Group

The Sierranus Group is composed of 3 species ( sierranus , arborea , and radocantans ). Like the Sequoia Group, all Sierranus Group species have a single spine on the posterior margin of the forefemur, a pair of prosternal spines, and the entire male tegmen ivory or white. The male subgenital plate has lateral carinae that converge to the apex, which is devoid of styli, petal-like and often reflexed. The stridulatory file tooth density is the highest of all Neduba species groups (59–77 teeth/mm), and this character alone separates it from all Sequoia Group species except N. inversa . The Sierranus Group is distributed in the central and northern Sierra Nevada while the Sequoia Group occupies the southern portions of that mountain range ( Figs. 8 , 19 ). Within this Group are morphologically cryptic species defined by song and/or karyotype. Body part measurements and stridulatory files offer the only means to identify males that lack song data. Females may also be identified by body part measurements and sometimes the shape of the subgenital plate. Species are parapatric in the Sierra Nevada ( Fig. 19 ) and thus geography will serve to narrow species possibilities. Molecular data show hybridization ( Fig. 4 ) between species with adjacent ranges.

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 5. Male calling songs of the Castanea, Lucubrata, Sierranus, and Sequoia Groups. A. N. castanea, B. N. macneilli, C. N. lucubrata, D. N. sierranus, E. N. radocantans, F. N. arborea, G. N. inversa, H. N. prorocantans, I. N. sequoia, J. N. duplocantans. 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 12. Female subgenital plates of Lucubrata (A), Sierranus (B–D), and Sequoia (E–H) Group species.

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

FIGURE 23. N. lucubrata male and female habitus, calling song, male and female terminalia, karyotype.