Zoologischer Anzeiger 276 (2018) 57e70 Contents lists available at ScienceDirect Zoologischer Anzeiger journal homepage: www.elsevier.com/locate/jcz Reasearch paper Comparative morphology of antennae in Cicadoidea (Insecta: Hemiptera), with respect to functional, taxonomic and phylogenetic implications * Xu Wang, Qinglong Li, Cong Wei Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Entomological Museum, Northwest A&F University, Yangling, Shaanxi 712100, China article info abstract Article history: The antennae of 25 cicada species were examined using light and scanning electron microscopies, with Received 14 April 2017 particular attention given to the structures and arrangement of antennal sensilla in phylogenic analysis. Received in revised form Eight morphologically different types of sensilla were observed: sensilla trichodea (subtypes I, II and III), 15 May 2018 sensilla basiconica, sensilla coeloconica (subtypes I, II and III), sensilla styloconica, foramen olfactorium, Accepted 15 May 2018 sensilla cavitata-peg (subtypes I and II), sensilla campaniformia and cuticular spines. The arrangement of Available online 23 August 2018 antennal sensilla tends to be a highly regular distribution model, i.e., sensilla trichodea and sensilla basiconica mainly spread in the scape and pedicel, while sensilla coeloconica, foramen olfactorium and/ Keywords: fl Cicadomorpha or sensilla styloconica merely spread in the agellum. The overall topology of phylogeny of Cicadidae Cicadidae based on antennal characters using PAUP, WinClada and IQtree analyses is compatible with the classi- Antennal sensilla fication of previously related studies, but shows that the genus Karenia Distant, 1888 is more allied to the Phylogenic analysis members of Cicadinae, and that the tribe Cicadatrini Distant, 1905 is located in the subfamily Cica- Cicadatrini dettinae instead of Cicadinae, which is consistent with the results of a recent molecular phylogenetic Karenia study of Cicadidae. The results imply that the traditional grouping of Cicadinae and Cicadettinae based on the presence or absence of timbal covers is unsound, which also supports related previous analyses based on morphology of Cicadidae. Related genera and tribes in Cicadidae need to be further addressed by phylogenetic analysis based on more morphological features combined with molecular data. © 2018 Elsevier GmbH. All rights reserved. 1. Introduction Cicadidae comprises all extant species of cicadas, except the two species of Tettigarctidae. Representing approximately 3208 described species the super- Moulds (2005) traced the phylogenetic relationships among family Cicadoidea is one of the lineages of Hemiptera, which are subfamilies, tribes and genera in Cicadidae based on morphological well known for the loud calling songs generated by the male adults characters, and divided Cicadidae into three subfamilies, i.e., Cica- (Sanborn 2013). The higher classification of Cicadoidea has been dinae Latreille, 1802, Cicadettinae Buckton, 1889, and Tettigadinae based mainly on characters connected with the sound-production Distant, 1905. However, Sanborn (2013) use the name Tibicininae organs and related morphological structures (Duffels 1993). Two Distant, 1905 instead of Tettigadinae, because Tettigadinae is a ju- families, Tettigarctidae and Cicadidae, are currently recognised in nior synonym of Tibicininae, although the type genus Tibicina of Cicadoidea (Moulds 2005; Sanborn 2013). The Tettigarctidae com- Tibicininae had been removed to Tettigadinae in the revised clas- prises only one extant genus, Tettigarcta White, 1845 (including two sification of Moulds (2005). More recently, Marshall et al. (2018) species confined to Australia), and five genera known only from reconstructed a molecular phylogeny of the cicadas with a review fossils, which are incapable of sound production similar to the of tribe and subfamily level classification, and four subfamilies are calling songs produced by other cicadas (Moulds 1990). The proposed. i.e., Cicadinae, Cicadettinae, Tibicininae, and Tettigo- myiinae, Distant, 1905, in which the tribes Tibicinini and Tettigadini are included in Tibicininae, thus, no appeal is need to suppress Tibicininae. The relationships concerning consensus in some taxa at * Corresponding author. tribe, subtribe and genus level of Cicadidae have remained E-mail address: [email protected] (C. Wei). https://doi.org/10.1016/j.jcz.2018.05.003 0044-5231/© 2018 Elsevier GmbH. All rights reserved. 58 X. Wang et al. / Zoologischer Anzeiger 276 (2018) 57e70 controversial. For example, Boulard (1973, 1976a, b) removed five 2.2.2. Scanning electron microscopy (SEM) genera that lack timbals to a newly erected the family Platypediidae The removed antennae were immersed in phosphate buffer Kato, 1932 from Tibicinidae Distant, 1905, in which Karenia Distant, solution (PBS 0.1 M, pH 7.2) in centrifuge tubes for about 2 h. After 1888 was included. However, Boulard (1988) disbanded Platype- cleaned by ultrasonic oscillation device in PBS for 1 min, they were diidae and replaced Karenia to Tibicininae. Later, Moulds (2005) transferred to 2.5% glutaraldehyde (PBS, 0.1 M, pH 7.2). After the attributed Karenia to Cicadettinae. However, this genus and other antennae were immersed in glutaraldehyde at 4 C for 12 h, they probably related taxa were actually not included in the morpho- were rinsed five times in PBS (0.1 M, pH 7.2), and then dehydrated logical phylogenetic analyses of Moulds (2005). Marshall et al. in a graded ethanol series and 100% acetone. Then, the samples (2018) removed Karenia to Cicadinae from Cicadettinae according underwent critical point drying and were sputter-coated with gold. to their molecular phylogenetic analysis, although the exact Examinations and photographs were taken under a JEOL JSM-6360 placement of Karenia, along with the position of the Dundubiini LV scanning electron microscope at 15 kV. taxa, is poorly supported. Another example is the controversy over the systematic position of the tribe Cicadatrini Distant, 1905. The 2.2.3. Choice of outgroup genus Mogannia Amyot and Audinet-Serville, 1843 had been put in Within the Cicadoidea, the Tettigarctidae is widely considered to the tribe Moganniini Distant, 1905, and Cicadatra Kolenati, 1857, have several synapomorphic character states, leading it to be the Psalmocharias Kirkaldy, 1908 and Nipponosemia Kato, 1925 (Nip- sister group of all other cicadas (Evans 1956, 1963; Moulds 1990, ponosemia is now a junior synonym of Vagitanus Distant, 1918 (Lee 2005). In this regard, T. crinita was chosen as the outgroup for the 2014) had been attributed to the tribe Cicadini Latreille, 1802 Cicadidae in our study. (Duffels and van der Laan 1985; Chou et al. 1997). Lee and Hayashi (2004) transferred Psalmocharias and Nipponosemia (¼Vagitanus) into the tribe Moganniini. Latter, Lee and Hill (2010) synonymized 2.2.4. Characters the tribe Moganniini Distant, 1905 with their newly erected tribe Forty-two adult characters (see below) of the 25 representative Cicadatrini Distant, 1905, and remained Cicadatrini in the subfamily species were derived from antennae. All multistate characters were Cicadinae. However, Chen et al. (2012) noted that the systematic treated as unordered because alternative arrangements were position of the Cicadatrini (represented by Mogannia) remains considered equally plausible. These multistate characters were questionable, because it shares more common morphological transformed into numerical attributes (e.g., 0, 1 and 2…) repre- characters with some groups in Cicadettinae. Marshall et al. (2018) senting the different character states upon which we established attributed Cicadatrini to Cicadettinae according to their molecular the set of data (see Table 2). phylogenetic analysis. Various previous studies indicated that antennal characters 0 Number of flagellar segments: (0) four articulated segments; could be informative in tracing phylogenetic relationships among (1) five articulated segments; (2) distinctly more than five insects. Faucheux et al. (2006) found that stylus-shaped sensillum segments, with distal segmentation(s) undistinguishable. chaeticum is a primitive sensillum which only occurs in some lower 1 Scape: (0) straight; (1) curved apically. Lepidoptera. Li et al. (2013) found that the traditional classification 2 Pedicel: (0) about as long as width, gradually slightly thinner at superfamily and family level in Coleoptera are well supported by apically; (1) distinctly longer than width, distinctly con- phylogenetic analyses based on antennal characters. However, stricted medially; (2) distinctly longer than width, distinctly antennal characters have never been applied in any phylogenetic thickened apically. analysis in Cicadoidea, although some studies have been conducted 3 Flagellum: (0) segments of flagellum in similar diameter and on a couple of cicadas (Klein et al. 1988). length, with each segment short stick-shaped; (1) sharply Herein, we investigate the antennal morphology of represen- tapered apically, with distal segment generally shorter than tatives in Cicadoidea with particular attention given to antennal previous ones; (2) gradually tapered apically, with distal sensilla. We mainly aim to reveal the relationships among related segment very long and much slender. taxa based on phylogenetic analysis using the data set of antennal 4 Flagellar segment 1: (0) stick-shaped, distinctly constricted character attributes. medially; (1) clavate, tapered apically