Okanagana boweni Chatfield-Taylor and Cole 2020, new species
Creators: name: Chatfield-Taylor, Will
name: Cole, Jeffrey A.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Cicadidae
Okanagana
Okanagana boweni

description: Okanagana boweni Chatfield-Taylor and Cole, new species
Table 1 (measurements), Table 2 (song statistics), Table 3 (molecular vouchers), Fig. 1 (habitus), Fig. 2 (male timbal), Fig. 3 (male terminalia), Fig. 4 (female terminalia), Fig. 5 (calling song), Fig. 6 (geographic distribution), Fig. 7 (phylogenetic hypothesis). Zoobank ID: 9C190D25-DE35-406D-AC4C-803AF864F25C
Type material. HOLOTYPE: 1 male, USA, NV, Washoe Co., Pyramid Lake, Tamarack Beach, 39.91333 oN, 119.54083 oW, 1134 m, 10-VII-2019, JA Cole, J Bailey, W Chatfield-Taylor, JF Eguizabal leg., ex tamarisk, rabbitbrush, recording WCT3737, barcode JAC000000230, deposited at LACM, LACM ENT 456101.
PARATYPES: 1 female, same data as holotype, LACM; 1 male, same data as holotype, CAS; 1 male, 1 female, same data as holotype, DNA extractions SING0873, SING0874, LACM; 3 males, same data as holotype, SEMK; 1 male, USA, CA, Inyo Co., Lone Pine Campground, 7 miles west of Lone Pine on Whitney Portal Road, 36.5977 oN, 118.1838 oW, 1785 m, 9-VII-2008, JA Cole leg., ex Artemisia tridentata, DNA extraction SING0246, LACM; 1 male, same data as previous, CAS; 2 males, same data, SEMK; 1 male, CA, Inyo Co., Lone Pine 15 mi. S, 36.3981 oN, 118.0256 oW, 1129 m, 18-VI-1969, PM Jump leg., LACM; 1 male, CA, Inyo Co., Lone Pine Cp. Gr., 36.5971 oN, 118.1769 oW, 1744 m, 28-VI-1970, DS Verity leg., LACM; 1 male, CA, Inyo Co., Tinemaha Rd. 2 mi. E US 395 nr. Independence, 36.8563 oN, 118.2145 oW, 1165 m, 28-V-1978, N Lee leg., LACM; 5 males, CA, Lassen Co., Doyle 4.5 mi. S, 39.9792 oN, 120.0622 oW, 1219 m, 15-VI-1969, RR Snelling & RA Snelling leg., LACM (Supp. Table 1).
Description. Head width narrower than front of pronotum. Deep median groove in yellow triangle at base of epicranium continues between lateral ocelli to form the epicranial suture. Front strongly produced with a median sulcus. Frons hirsute with deep frontocylpeal suture. Supra-antennal plates orange (Fig. 1).
Lateral margins of pronotum distinctly subparallel with broad posterior margin entire, giving a quadrate aspect. Humeral angles broadly rounded, anterior angles acute. Pronotum completely bordered with yellow. Rugose ridges lateral to pronotal midline marked with variable amounts of brown or yellow. Anterior half of pronotum with strongly sulcate broad longitudinal yellow line. Mesonotum black, with broad yellow posterior margin and cruciform elevation partly (holotype) to completely (paratypes) yellow. Four yellow spots form a semicircle with yellow marks at base of each wing. Size and shape of mesonotal markings variable (extensive in holotype). Metanotum bordered by yellow that is interrupted by black anterior to timbals (Figs. 1, 2).
Forewings with yellow costa turning black and slightly fuscous past the node. Venation variegated with yellow to marginal cells (holotype) or mostly black (some paratypes). Posterior margin of membrane gently curved, wing tip rounded (feature visible only on spread, intact specimens). Basal cell opaque, varying from black (holotype) to yellow (some paratypes). Hind wings lightly fuscous at base. Wing membranes orange. Meso- and metasternum hairy, marked with black and yellow. Profemora striped black and yellow, other legs variably marked (Fig. 1).
Tergum sparsely hairy, shining black, with posterior margin of last two tergites variably bordered with yellow (Fig. 1). Male timbals with 2 major and 2 minor ribs (Fig. 2). Sternites yellow with extensive variable black markings edging posterior margins; in holotype, yellow markings are narrow at the center and broaden laterally, giving the impression of a central longitudinal black stripe bordered by two yellow stripes on the abdominal venter. The 7th abdominal sternite hourglass-shaped, medially constricted with rounded apical margins (Fig. 1).
Uncus in dorsal view diamond-shaped, formed from straight lateral margins that widen for one half to two thirds of the length and then converge towards the apex (Fig. 3 shows typical condition). In lateral view, upper surface with distinct curvature, not parallel with respect to lower surface. Hook forms abruptly after short and deep posteroventral excavation. Aedeagus elongated, attached at an angle perpendicular to the plane of the uncus with posterior edge distinctly incurved to varying degrees. Male valve roughly triangular with posterior edge slightly curved. Female with apical prongs on 7th abdominal sternite broad and rounded with a wide, faint secondary notch (Fig. 4).
Diagnosis. Okanagana boweni is a large-bodied species most similar to allopatric O. simulata in body size and habitus but to sympatric O. utahensis in color pattern (Fig. 1). Diagnosis of museum specimens may be accomplished by a suite of characters, some of which are visible on spread specimens with pulled genitalia and others on unprepared specimens.
In unprepared specimens a character combination is necessary for diagnosis of the three similar species. A quadrate pronotum with parallel lateral margins separates O. boweni and O. simulata from O. utahensis, which has an anteriorly constricted pronotum, and a broad longitudinal yellow sulcus on the anterior half of the pronotum separates O. boweni and O. utahensis from O. simulata, in which the sulcus is barely indicated and faintly marked (Fig. 1). Thus, O. boweni possesses both a quadrate pronotum with a broad yellow longitudinal sulcus. Less reliable diagnostic characters include the semicircle of mesonotal markings, which tend to be more extensive in O. boweni and O. utahensis compared with those of O. simulata, the head width narrower than the anterior margin of the pronotum in O. boweni but subequal in O. simulata, and the posterior pronotal margin appearing complete in O. boweni but incomplete in O. simulata due to a darkened median constriction in the latter (Fig. 1).
On prepared specimens the uncus and aedeagus are valuable characters for diagnosing the two species (Fig. 3). Uncus shape should be used in conjunction with other characters due to intraspecific variation that is found generally throughout Okanagana (WCT pers. obs.). In dorsal view, the uncus of O. boweni has parallel lateral margins that converge towards the apex with a distinct angle that begins at one half to two thirds of its length, compared with the gradually and smoothly curved lateral margins of O. simulata and O. utahensis. When exposed in lateral view, the aedeagus is a singular character that diagnoses O. boweni from both O. simulata and O. utahensis. The posterior edge of the aedeagus is long and incurved in O. boweni, forms an acute angle in O. simulata, and is uniformly straight and short in O. utahensis with its posterior margin situated perpendicular to the plane of the uncus (Fig. 3).
Female O. boweni may be diagnosed by the lack of the deep secondary notch on the 7th abdominal sternite found in O. simulata and to a lesser extent in O. utahensis females (Fig. 4). For O. utahensis without clearly indicated secondary notches, diagnosis may require examination of pronotal shape or the condition of the longitudinal sulcus (Fig. 1).
O. boweni is sympatric with O. utahensis but can be diagnosed from the latter in the field by the larger body size (Table 1) and quadrate aspect of the pronotum of O. boweni, in contrast with the smaller body size and trapezoidal aspect lent by the anterior convergence of the lateral pronotal margins in O. utahensis (Fig. 1). The morphology of the male (Fig. 3) and female (Fig. 4) terminalia are also diagnostic.
Bioacoustics. The male calling song of O. boweni is a continuous train of syllables with a single dominant frequency that is similar to the calls of both O. simulata and O. utahensis (Table 2; Fig. 5; see Chatfield-Taylor & Cole 2019). Amplitude modulation at a rate of 7.82 ± 0.47 s- 1 (n = 4) may elaborate the song structure (Fig. 5), and when this occurs a wavering quality is imparted to the song as it oscillates in loudness. Amplitude modulations often began or became more pronounced when males were disturbed or approached, behavior that was also observed in O. simulata and O. utahensis (JAC, pers. obs.).
Neither syllable rate (ANCOVA, P = 0.111) nor peak frequency (P = 0.653) varied with temperature. Songs differed significantly between species (MANOVA, P = 4.74x10 -4) but not between O. boweni populations (P = 0.543). Of the three species, O. utahensis was most divergent in song, but songs of O. boweni and O. simulata also differed significantly (P = 5.2x10 -3), differences that were again not explained by population (P = 9.08x10 -2). Per the methodology of Chatfield-Taylor and Cole (2019), the calls of O. boweni and O. simulata were separated by 0.09 standard deviations (SD) in parameter space while separation between O. boweni and O. utahensis ranged from 0.85 to 2 SD.
Distribution. The distribution extends from the southern extent of the Owens Valley in eastern California north to Pyramid Lake, Nevada (Fig. 6). This distribution coincides with a geologically defined region of major transform faulting (Carlson et al. 2013; Wesnousky 2005) that has been termed the Walker Lane (Locke et al. 1940). The Walker Lane extends from the Garlock Fault at the southeastern corner of the Sierra Nevada and Tehachapi Range, which forms the northern border of the Mojave Desert, northeast to the Pyramid Lake Block in Nevada, and northwest to the Northern California Shear Zone that borders the Modoc Plateau in northeastern California (Carlson et al. 2013; Smith 1962; Stewart 1988).
Etymology. The species is named after Charles Bowen, a naturalist from Belize who kindled the senior author’s interest in the biological sciences.
Seasonal occurrence. Available records indicate activity from late spring (28 May, N. Lee, LACM) through midsummer (10 July, holotype, LACM).
Habitat and notes. Habitat at the type locality is primarily alkali flats dominated by sages in the Tridentate group (Artemisia spp.) and tamarisk (Tamarix sp.; J. Bailey, pers. comm.). At the type locality males called from tamarisk and other available vegetation in their open habitat as they engaged in sing-fly behavior, while females were found exclusively on Artemisia tridentata. Besides O. boweni, we observed three other hooked uncus species in association with Artemisia tridentata during our 2019 field season: O. simulata, O. utahensis, and O. vanduzeei Distant. Hooked uncus taxa have been associated previously with Artemisia (Davis 1919; Kondratieff et al. 2002; Sanborn et al. 2002).
Molecular phylogenetics. Alignment lengths were 510 bp for 16S, 198 bp for ARD1 UTR, 414 bp for ARD1 CDS, 423 bp for EF1α exons, 305 bp for EF1α introns, and 1013 indel characters. PartitionFinder returned two partitions: 1) the HKY+I model applied to a partition consisting of the 3rd codon positions of coding regions and all noncoding regions, and 2) the F81 model applied to all first and second codon positions. The standard deviation of split frequencies was 3.63x10 -3, which indicated significant convergence of Markov chains.
A utahensis - vanduzeei clade resolved sister to a boweni - simulata clade (Fig. 7) with strong support (posterior probability 98%). Whereas the former pair were reciprocally monophyletic, O. simulata rendered O. boweni paraphyletic. A relatively long branch separated O. simulata from O. boweni.
description: Published as part of Chatfield-Taylor, Will & Cole, Jeffrey A., 2020, A new species of Okanagana from the Walker Lane region of Nevada and California (Hemiptera: Auchenorrhyncha: Cicadidae), pp. 515-530 in Zootaxa 4868 (4) on pages 517-525, DOI: 10.11646/zootaxa.4868.4.3, http://zenodo.org/record/4418072