Ankylopterygini Navás, 1910

Wu, Jingyu & Liu, Xingyue, 2024, Systematics of the green lacewing tribe Ankylopterygini Navás, 1910 (Neuroptera: Chrysopidae: Chrysopinae) from China, Zootaxa 5540 (1), pp. 1-169 : 9-14

Tribe Ankylopterygini Navás, 1910

Ancilopterygino Navás, 1910a: 59.

Ankylopterygini Navás , 1913: 293.

Diagnosis. Body small to large. Body length 5.6–21.0 mm, forewing length 7.5–27.0 mm, hindwing length 6.7–25.5 mm. This tribe is characterized by the following characters: the head sometimes with spots on the frons, clypeus and gena, the large prominent compound eyes, the antennal scape sometimes with brown stripe on the outer or inner side, the scape wider than pedicel and flagellum, the sickle-shaped mandibles without basal teeth, the maxillary and labial palpi usually marked, the terminal palpomere pointed or not, the pronotum sometimes with small brown spots anterolaterally, the mesonotum and metanotum with brown markings or not, the legs sometimes marked with black spots on tibia and with long pale setae, the pretarsal claws with basal dilation, the forewing sometimes with brown shadings on gradates, CuP, etc., the costal area strongly or feebly broadened basally, the dark or indistinct pterostigma, the cell m1 smaller than m2, the present or absent cell im, the gradates in two or more divergent rows, the basal crossvein of inner gradate series meeting Psm or not, the cell c1 smaller than c2, the opened or closed cell dcc, the hindwing usually without shadings, the abdomen with dense setae, the male tergum IX fused with ectoproct, the male sternum VIII fused with sternum IX or not, the ovoid callus cerci, the male genitalia without tignum and gonapsis, the arcuate gonarcus, the entoprocessus always attached with gonarcus, the pseudopenis not attached with entoprocessus or the arcessus attached to the entoprocessus, the female subgenitale distinctly or slightly bilobed apically, the thick or thin spermatheca, the long or short or absent vela, the deep or shallow or absent ventral impression, and the long curved duct.

Distribution. Palaearctic, Afrotropical, Australian, Oriental and Nearctic regions.

Remarks. In Brooks & Barnard (1990), based on the male genitalia being without tignum and gonapsis as well as being pointed terminal palpomere of maxillary and labial palpi, the tribe Ankylopterygini included only five genera: Ankylopteryx Brauer, 1864 , Retipenna Brooks, 1986 , Parankylopteryx Tjeder, 1966 , Semachrysa Brooks, 1983 and Signochrysa Brooks & Barnard, 1990 . Garzón-Orduña et al. (2019) and Winterton et al. (2019) reconstructed the phylogeny of Chrysopidae and the results showed that Tumeochrysa Needham, 1909 , Nineta Navás, 1912 and Chrysopidia Navás, 1910 are closely related to Ankylopterygini . The species of Tumeochrysa , Nineta and Chrysopidia do not possess a pointed terminal palpomere of the maxillary and labial palpi, but the male genitalia in these species also lack tignum and gonapsis as in typical Ankylopterygini species. Breitkreuz et al. (2022) formally transferred Nineta , Tumeochrysa and Chrysopidia to Ankylopterygini .

Key to genera of Ankylopterygini

1. Terminal palpomere of maxillary and labial palpi finely pointed................................................ 2 Terminal palpomere of maxillary and labial palpi flat and obtuse................................................ 3

2. Body small; gradates of forewing and hindwing in two or three divergent rows; meso- and metatibia without spur Chrysopidia Body large; gradates of forewing and hindwing in three to five divergent rows; meso- and metatibia with a spur Tumeochrysa

3. Costal area of forewing obviously widened................................................................. 4 Costal area of forewing not obviously widened.............................................................. 5

4. Pterostigma of forewing brown or black; male entoprocessus fused apically; pseudopenis not attached with entoprocessus or gonarcus................................................................................... Ankylopteryx Pterostigma of forewing indistinct; male entoprocessus not fused; arcessus attached with entoprocessus and gonarcus.............................................................................................. Parankylopteryx

5. One black spot present between antennae; mesopleura usually with black spots; male sternum IX elongated and exceeded ectoproct; ectoproct with two clusters of setae...................................................... Signochrysa No interantennal spot; mesopleura without spots; male sternum IX not elongated; setae on ectoproct not concentrated..... 6

6. Frons usually without spots; arcessus covered with membrane, without dense setae.......................... Retipenna Frons always with three dark spots in a row; arcessus not covered and with four setae...................... Semachrysa

Genus Ankylopteryx Brauer, 1864

Ankylopteryx Brauer, 1864: 899 . Type species: Chrysopa venusta Hagen, 1853: 141 . Subsequently designated by Tjeder, 1966:

497. Ethiochrysa Fraser, 1952: 57 . Type species: Ethiochrysa polychlora Fraser, 1952: 57 . Monotypy. Sencera Navás, 1924 [1925]: 26. Type species: Sencera scioneura Navás, 1925: 27 . Original designation and monotypy. syn.

nov.

Diagnosis. Body small to medium-sized. Body length 7.0–9.0 mm, forewing length 10.0– 11.4 mm, hindwing length 9.7–11.3 mm. This genus is characterized by the presence of the head always marked with black spots on the frons, clypeus and gena, the antennal scape with blackish-brown stripe on the outer side, the scape wider than pedicel and flagellum, the maxillary and labial palpi usually black on the outer side, the pointed terminal palpomere, the pronotum with small brown to black spots anterolaterally, the mesonotum always with brown markings, the metanotum not marked, the legs sometimes marked with black spot on the pro-, meso- or metatibia, the pretarsal claws with basal dilation, the broad forewing marked with brown suffusions, the basally broad costal area, the distinct pterostigma, the present or absent cell im, the gradates in two divergent rows, the basal crossvein of inner gradate series meeting Psm, the opened or closed cell dcc, the male sternum VIII fused with sternum IX, the apically fused entoprocessus, the pseudopenis wide basally and tapering apically, the gonosaccus with few gonosetae, the apically bilobed female subgenitale, the thick spermatheca, the absence of the vela, the almost reduced ventral impression, and the long coiled duct.

Distribution. Afrotropical, Australian and Oriental regions.

Remarks. Tjeder (1966) established a subgenus for Ankylopteryx , i.e., Parankylopteryx . Brooks & Barnard (1990) elevated it to a genus. Parankylopteryx and Ankylopteryx have similar external morphological characters, especially the forewing marked with brown suffusions and obviously widened costal area. However, Parankylopteryx has the indistinct pterostigma, unfused entoprocessus, and the arcessus attached with the gonarcus and entoprocessus, which is different from the fused entoprocessus and detached pseudopenis in Ankylopteryx .

Sencera was established as a subgenus based on the absence of forewing cell im (Navás 1925). Sencera was keyed as a genus by Brooks (1983) and then demoted to subgeneric rank by Brooks & Barnard (1990). Currently, this subgenus contains only one species, i.e., Ankylopteryx anomala Brauer, 1864 ( Breitkreuz et al. 2015). In fact, the shape of cell im of Ankylopteryx is variable: A. gracilis has extremely narrow and triangular im, but the cell im of A. octopunctata candida is broad and quadrate. We speculate that the absence of the cell im is an extreme variation. The phylogenetic analyses conducted herein shows that this species is well nested within genus Ankylopteryx ( Fig. 93 ). Hence, we treat Sencera Navás, 1925 as a junior synonym of Ankylopteryx Brauer, 1864 .

Species of Ankylopteryx show a high diversity both in external morphological and genital characters. The markings on the head, thorax and wings, and the shape of entoprocessus are important identification characters. However, these characters may not be stable within a species. Taking A. octopunctata candida as an example, after examination of many specimens from different places, we found that some specimens would randomly lose certain characters, such as: interantennal spots, reddish stripe in frons, markings on wings, etc. Moreover, this species shows a high degree of variations in projections of apex of male entoprocessus. Through morphological comparison and species delimitation with COI gene fragments, we confirm that these specimens all belong to A. octopunctata candida . Such intraspecific differences have not yet been found in other species.

Key to species of Ankylopteryx in China *

1. Cell im of forewing absent...................................................................... A. anomala Cell im of forewing present............................................................................. 2

2. Cell im of forewing narrow triangular or ovoid.............................................................. 3 Cell im of forewing quadrate and broad.................................................................... 5

3. Cell im of forewing triangular; brown shadings concentrated on basal 1/3 of wings....................... A. ferruginea Cell im of forewing extremely narrow and ovoid; brown shadings of wings scattered................................ 4

4. Dark spots present between antennae; most of crossveins of wings pale, only radial crossveins, basal two inner gradate series and CuP brown................................................................................ A. gracilis No spots present between antennae; almost all crossveins of wings brown and with brown shadings.......... A. doleschalii

5. Forewing and hindwing with brownish vittae along posterior margin.................................... A. delicatula Wings without vittae along posterior margin................................................................ 6

6. Metanotum brown; forewing and hindwing with conspicuous markings along posterior margin from CuP and spanning five crossveins............................................................................. A. magnimaculata Metanotum partially brown or without brown spots; markings along posterior margin small and pale................... 7

7. Many brown shadings scattered on forewing and hindwing............................................ A. diffluens Forewing with brown shadings on pterostigma, basal crossvein of inner gradate series and CuP; hindwing sometimes with small brown shadings on posterior margin crossveins.............................................................. 8

8. Scape with brown stripes on outer and inner side; metascutellum with marking shaped like mountains A.montipunctata sp.nov. Scape with brown spots on outer side or not; metanotum without spots........................................... 9

9. Scape without brown spots; frons without spots............................................................ 10 Scape with brown spots on outer side; frons with spots....................................................... 11

10. Metascutum with brown spots; male entoprocessus sudden narrowed at middle and projected at tip........ A. stena sp. nov. Metanotum without spots; male entoprocessus curved and wide at tip.......................... A. hainanensis sp. nov.

11. Supra-antennal area marked with red spots; V-shaped black spots present between antennae; mesoprescutum and mesoscutum reddish brown, metascutum with reddish-brown spots; male entoprocessus short and curved................ A. rubrocincta Almost quadrate black spots present below antennae; frons with reddish spots; mesonutum all brown or only anterolateral angle of mesoscutum brown, metascutum with small brown spots; male entoprocessus not curved........ A. octopunctata candida

* A. quadrimaculata is not included in the key.

Figures

FIGURE 93. ML tree of Ankylopterygini based on COI gene fragments (part). Numbers near each node are bootstrap value (%).