Introrsa yaoquensis Dai and Zhang

Dai, Wu, Cui, Wei, Xiao, Bin & Zhang, Yalin, 2010, A new genus and species of Old World Opsiini (Hemiptera: Cicadellidae: Deltocephalinae), with a key to genera and species checklist for the tribe, Zootaxa 2607, pp. 55-68 : 60-62

Introrsa yaoquensis Dai and Zhang , sp. nov.

Figs. 1–9

Male 8.2–8.5mm.

Body bright yellow. Crown with transverse orange convex fascia at anterior margin, apex with pair of similar black spots ( Figs. 1 , 3 ). Pronotum with six orange longitudinal lines on posterior part. Scutellum with ambiguous orange markings and black at apex ( Figs. 1, 2 ).

Male pygophore with two small caudal and caudoventral processes ( Fig. 4 ). Subgenital plate broad basally and narrowed to digitate apex ( Fig. 5 ). Connective stem longer than arms ( Fig. 6 ). Style with basal half wide, narrowing to the midlength with apical half narrow, lateral lobe slightly developed ( Figs. 6, 7 ). Aedeagus with each shaft with long basal process at inner margin extended to apex of shaft, and with small basal tooth at ventral margin ( Fig. 8, 9 ).

Type material. Holotype 3, China: Yunnan, Mengyang, 750m, 6 June 1991, Wang Yinglunn and Tian Rungang; Paratypes: 103, Yunnan, Mengyang, 750–800m, 6–9 June 1991, Wang Yinglunn and Tian Rungang; 23,Yunnan, Menglun, 19 May 1991, Wang Yinglunn and Tian Rungang; 23, Yunnan, Mengla, Yaoqu, 11 May 1991, Liu Guangchun and Cai Wanzhi; 13, Yunnan, Mengla, Longmen, 930m, 17 May 2009, Cui Wei, at light; 13, Yunnan, Mengla, Yaoqu, 800m, 6 June 2009, Ma Libin; 13, Yunnan, Xishuangbanna, Jinghong, 515m, 14–16/ 22–25 May 1974, Chou Io and Yuan Feng; 13, Yunnan, Xishuangbanna, Mengla, 620–650m, 9 June 1959, Zhang Facai, at light.

Etymology. The specific name is derived from the type locality.

Chromosome numbers and type of chromosomal sex determination. At prophase, the chromosomes show a bouquet-like structure: the end of the chromosomes assemble at one side of the karyolemma ( Fig. 10 ). Meiotic metaphase I (MI) cells each show five autosomal bivalents and a univalent X chromosome. Two of the bivalents are bean shaped and the other three are thinner, of which one is bigger than others. The X chromosome is close in size to the medium-sized half bivalents and positioned at a distance from bivalents ( Fig. 11 ). During meiotic Anaphase I the autosomes move synchronously towards the poles, while the X chromosome does not divide and lags behind ( Fig. 12 ). The first meiotic division is reductional, so two daughter metaphase II (MII) cells show six and five chromosomes respectively ( Fig. 13 ). Hence, the sex determination system is XO/XX and the karyotype of the species is 2n=12(10+XO).

Note. Chromosome numbers in the family Cicadellidae vary from 2n=8 to 2n=28 with the predominant karyotypes of 2n=16, 18, 20, and 22. For Opsiini , low chromosome numbers are typical, as 3 known species belonging to 2 genera ( Hishimonus , Opsius ) of this tribe have karyotypes of 2n=12, 10, respectively ( Emeljanov & Kirillova, 1989). The species Introrsa yaoquensis has same chromosome numbers and karyotype as the genus Opsius . Moreover, All 4 studied species of Opsiini show presence of 1 or 2 large bivalents and absence of small chromosomes. Studies of the chromosomes of other Opsiini , particularly representatives of other subtribes, are needed to determine whether these chromosomal characters are useful diagnostic features for members of this tribe.

Figures

FIGURE 3. Introrsa yaoquensis sp. nov. Face.

FIGURES 1 – 2. Introrsa yaoquensis sp. nov. 1. Habitus, dorsal view; 2. Habitus, lateral view.

FIGURES 4 – 9. Introrsa yaoquensis sp. nov. 4. Pygophore, lateral view; 5. Genital valve and subgenital plate, ventral view; 6. Connective and style; 7. Apical half of style, lateral view; 8. Aedeagus, lateral view; 9. Aedeagus, ventral view.

FIGURES 10 – 13. Meiotic chromosomes of males of Introrsa yaoquensis. 10. Prophase; 11. Meiosis metaphase I, n = 6, XO; 12. Meiosis anaphase I, sex chromosome lag behind autosomes; 13. Meiosis metaphase II, show two types of cells with five and six chromosomes.