Cerapanorpa, Gao, Chao, Ma, Na & Hua, Bao-Zhen, 2016

Gao, Chao, Ma, Na & Hua, Bao-Zhen, 2016, Cerapanorpa, a new genus of Panorpidae (Insecta: Mecoptera) with descriptions of three new species, Zootaxa 4158 (1), pp. 93-104 : 94-97

Cerapanorpa gen. nov.

Type species: Panorpa obtusa Cheng, 1949 .

Etymology. The generic epithet derives from the Greek, cera (horn), and Panorpa , referring to the single anal horn on tergum VI of males and being closely related to Panorpa .

Diagnosis. Cerapanorpa gen. nov. can be distinguished from other genera of Panorpidae by the following characters: (1) tergum VI of males with a digitate anal horn; (2) aedeagus with dorsal valves sclerotized and prolonged caudally, ventral valves extremely short and membranous; (3) parameres simple, seldom furcated, bearing spines on apical half; (4) hypandrium (sternum IX) composed of a very short basal stalk and a pair of elongate hypovalves; (5) female genital plate complicated and developed, with a broad main plate, bearing a pair of basal plates each on dorsal and ventral sides and the well-developed elongate rod-like axis prominently extending beyond the main plate.

Description. Head almost uniformly black on frons, vertex and occiput. Rostrum yellowish brown to black anteriorly, relatively paler on lateral sides. Thorax dark black on dorsum, pale yellow on pleura ( Fig. 1 A, B). Pronotum with black bristles along its anterior margin. Legs pale yellow, tarsomeres darkening toward the apex. Wing membrane hyaline, often with dark markings, seldom with yellow tinge. Abdominal segments I −VI brownish black on terga, paler on sterna and pleural membrane; segments VII and IX yellowish brown. In males, posterior margin of tergum III slightly produced posteriorly into a flat semicircular notal organ; postnotal organ on tergum IV small and pointed forward ( Fig. 1 C); tergum VI with a digitate anal horn on the posterior margin ( Fig. 1 D); basal half segment VII considerably thinner than apical half, dilated apically; segment VIII as long as segment VII, gradually dilated apically. Genital bulb oval ( Fig. 1 F, G); epandrium (tergum IX) slightly tapering toward the apex, with a shallow to deep U-shaped terminal emargination; hypovalves elongate, with the medial margin bearing stout bristles; gonocoxite usually with a group of black setae on the meso-apex, and a small subapical tooth on medial margin; gonostylus shorter than gonocoxite, medially curved, ending in an acute apex, with a flat cup-like basal process and a small mesal tooth on inner margin ( Fig. 1 F); parameres sclerotized, simple or seldom furcate, usually bearing spines apically ( Fig. 1 I); aedeagus with a pair of elongated dorsal valves, a pair of membranous ventral valves, and a prominent lateral process ( Fig. 1 H). In females, subgenital plate lingulate, widest at middle, bearing long setae along outer margins ( Fig. 2 C); genital plate consisting of a broad main plate with two pairs of membranous basal plates on its dorsal and ventral sides and an elongate median axis ( Fig. 2 D–F); posterior arms weakly sclerotized; ventral basal plates fused mesally; dorsal basal plates relatively smaller and separated; the rodlike axis elongate and curved dorsad, prominently protruding beyond the main plate and bifurcated in anterior half.

Distribution. The Oriental ( China) and Palearctic Regions ( China, Japan, Korea and Russia).

Remarks. Cerapanorpa gen. nov. currently comprises 22 species, including 19 new combinations transferred from Panorpa , and three new species, Cerapanorpa liupanshana sp. nov. from Ningxia, and C. protrudens sp. nov. and C. sinuata sp. nov. from Shaanxi .

In the North American Panorpa rufescens species group, tergum VI of males is also produced posteriorly into a flat or conical projection, which is also called an anal horn ( Esben-Petersen 1921; Carpenter 1931; Byers 1993). However, the so-called anal horn of the P. rufescens group differs greatly from the digitate (finger-like) anal horn of Cerapanorpa gen. nov. in morphology.

Based on our recent phylogenetic analysis of molecular data ( Hu et al. 2015), the species of Cerapanorpa gen. nov. constitute a well-supported clade, which diverges distantly from the North American species, indicating that the so-called anal horns are likely homoplasious characters between Cerapanorpa gen. nov. and the P. rufescens group.

Species of Cerapanorpa gen. nov. usually inhabit elevated open areas in mountainous regions. The adults often occur in large populations, and some species may be especially abundant in dense Artemisia (Asteraceae) vegetation. The wings are held flat as a V-shape over the abdomen at rest ( Fig. 1 A, B), unlike the roof-like wings of Furcatopanorpa (Ma & Hua 2011) and a few species of Panorpa . The epedaphic larvae of C. obtusa ( Cheng, 1949) inhabit the surface of the ground, and bear long setae on both the head and the body ( Jiang & Hua 2015).

It should be noted that P. flavipennis Carpenter, 1938 is not included in the new genus, although the species was regarded as belonging to the P. centralis group previously by Carpenter (1938) and Cheng (1957). Carpenter (1938) mentioned that the species “possesses a single anal horn on 6th abdominal segment” in the original description, and clearly assigned the species to the centralis group. In a revision of the Chinese Mecoptera, Cheng (1957) specifically described the “single anal horn on 6th abdominal segment very short”, and presented an illustration of the so-called anal horn ( Cheng 1957: fig. 13), which is in fact only a very short lobe and definitely not the anal horn as we treat in this paper. Ironically, both Carpenter (1938) and Cheng (1957) noted that the wing membrane of P. flavipennis is deep yellow, markedly different from the colorless or lacteous wing membrane of the new genus. More importantly, the male genitalia of P. flavipennis differ from those of Cerapanorpa gen. nov. in the more slender hypovalves and the possession of distinct lobes on the gonostylus. In addition, the female genital plate ( Carpenter 1938: fig. 12) is considerably different from that of the new genus in gross morphology.

Figures

FIGURE 1. Cerapanorpa obtusa. (A) and (B) Male and female habitus, photo by Lu Jiang; (C) notal organ and postnotal organ of male, lateral view; (D) abdominal segments V – IX of male, lateral view (from Ma et al. 2014); (E) tergum VI of male, dorsal view, showing the anal horn; (F) and (G) genital bulbs, ventral and dorsal views; (H) aedeagus, ventral view; (I) left paramere, ventral view. Abbreviations: Ae, aedeagus; AH, anal horn; BP, basal process; DV, dorsal valve; Ep, epandrium; Gcx, gonocoxite; Gs, gonostylus; Hv, hypovalve; LP, lateral process; MT, median tooth; NO, notal organ; Pm, paramere; PnO, postnotal organ; VV, ventral valve. Scale bars: C, F, G = 0.20 mm, D = 1.00 mm, E = 0.50 mm, H, I = 0.10 mm.

FIGURE 2. Female of Cerapanorpa obtusa. (A) and (B) Abdominal segments VIII – XI, lateral and ventral views; (C) subgenital plate, ventral view; (D) – (F) genital plate, ventral, lateral and dorsal views (D from Ma et al. 2014). Abbreviations: Ax, axis; DBP, dorsal basal plate; MP, main plate; PA, posterior arm; VBP, ventral basal plate. Scale bars: A, B, E = 0.20 mm, C = 0.10 mm, D, F = 0.25 mm.