Idaea rectangularis Cheng & Han, 2023

Cheng, Rui, Xue, Da-Yong, Jiang, Nan & Han, Hong-Xiang, 2023, Review of the Idaea proximaria complex (Lepidoptera, Geometridae, Sterrhinae) with descriptions of four new species, ZooKeys 1169, pp. 293-305 : 293

Idaea rectangularis Cheng & Han sp. nov.

Figs 8 , 9 , 20 , 27 , 31

Type material.

Holotype, ♂, China: Guangxi (IZCAS): Jinxiu, Linhaishanzhuang, 1000 m, 2.VII.2000, leg. Li Wenzhu, slide no. Geom-5160. Paratypes: Guangxi (IZCAS): 1♂2♀, same data as holotype, slide no. Geom-5161(♀); 1♀, Huanjiang, Yangmeiao, 1189 m, 18-22.VII.2015, leg. Jiang Nan, slide no. Geom-5187. Fujian (IZCAS): 1♀, Chongan, Xingcun, Guadun, 900-1160 m, 8.VII.1963, leg. Zhang Youwei; 1♀, Wuyishan, Dazhulan, 1150 m, 28.VII.2006, leg. Xue Dayong, slide no. Geom-5182.

Diagnosis.

Compared to I. proximaria , the forewing apex of I. rectangularis is somewhat sharper, and the first segment of male hind tarsus is darker. The male genitalia of I. rectangularis are similar to those of I. proximaria , but can be differentiated by the following characters: the anellus is smaller than that of I. proximaria , and the anterior half lacks spines on the lateral margin in I. rectangularis whereas these are present in I. proximaria ; the valva possesses a small blunt finger-like process in I. rectangularis , whereas in I. proximaria there is only a protrusion which does not form a process; the slightly concave uncus is also different. The aedeagus is distinguished by the number of the cornuti, which is five in I. rectangularis , including one right-angled spine, but only one or two in I. proximaria . In the female genitalia, the region surrounding the ostium is not totally sclerotised, with a separate lamella postvaginalis. The ductus bursae lacks a bag-like process in I. rectangularis but it is present in I. proximaria .

Description.

Head. Antennae ciliate in male, filiform in female. Frons, labial palpus, vertex identical to I. proximaria .

Thorax. Hind leg similar to that of I. proximaria , but first segment of male hind tarsus blackish grey. Forewing length: male 10 mm, female 10-11 mm. Wing pattern and markings similar to those of I. proximaria , except that the apex of the male forewing protrudes further.

Abdomen. Male genitalia. Uncus spatulate, posterior margin slightly concave. Gnathos developed, tapering. Valva long and slender, with a sclerotised ridge at middle; apex rounded and setose; dorsal margin slightly concave at middle, with a faint subapical protuberance; ventral margin deeply concave near middle, with a small finger-like blunt process. Saccus blunt. Anellus a large sclerite, posterior half rounded, anterior half an inverted trapezoid. Aedeagus stout, terminal two-thirds sclerotised and broadened; cornutus with five spines, one larger than the rest and right-angled; vesica with a scobinate area.

Female genitalia. Ovipositor lobes with a small ventral protrusion. Apophyses posteriores ~ 2 × length of apophyses anteriores. Lamella postvaginalis a laterally elongate sclerite, wrinkled. Lamella antevaginalis shapeless, but with left side of ostium strongly sclerotised, scobinate anteriorly. Ductus bursae very broad, wrinkled, the large posterior half decorated with long spines, anteriorly slightly sclerotised; an elongate posteriorly diverging appendix bursae present. Corpus bursae small, rounded, decorated with an oval spinose patch.

Distribution.

China (Guangxi, Fujian).

Etymology.

This species is named from Latin word Idaea rectangularis , which refers to the one right-angled cornutus.

Figures

Figures 1 - 15. (1 - 2) Male hind tibia and tarsus of Idaea proximaria 1 lateral view 2 medial view. (3 - 14) Adults of Idaea proximaria complex 3 - 7 I. proximaria 3 male, Jiguanshan, Sichuan 4 female, Baoxing, Sichuan 5 - 7 Jinsixia, Shaanxi 5 - 6 male 7 female 8 - 9 I. rectangularis sp. nov. 8 holotype, male, IZCAS 9 paratype, female, IZCAS 10 I. rectispina sp. nov., holotype, male, IZCAS 11 - 12 I. setosa sp. nov. 11 holotype, male, IZCAS 12 paratype, female, IZCAS 13 I. linearis sp. nov., holotype, female, IZCAS 14 I. craspedota. 15 Neighbour-Joining (NJ) tree of selected Idaea proximaria complex based on the Kimura two-parameter model. Scale bar: 1 cm (3 - 14).

Figures 16 - 27. (16 - 23) Male genitalia of Idaea proximaria complex 16 - 19 I. proximaria 16 - 17 Shizipo, Sichuan 18 - 19 Jinsixia, Shaanxi 20 I. rectangularis sp. nov., holotype 21 I. rectispina sp. nov., holotype 22 I. setosa sp. nov., holotype 23 I. craspedota. (24 - 27) Aedeagus of I. proximaria complex 24 - 26 I. proximaria 24 Dashuigou, Sichuan 25 Shizipo, Sichuan 26 Jinsixia, Shaanxi 27 I. rectangularis sp. nov., holotype. Scale bars: 1 mm.

Figures 28 - 34. (28 - 29) Aedeagus of I. proximaria complex 28 I. rectispina sp. nov., holotype 29 I. setosa sp. nov., holotype (30 - 34) Female genitalia of I. proximaria complex 30 I. proximaria 31 I. rectangularis sp. nov., paratype 32 I. setosa sp. nov., paratype 33 I. linearis sp. nov., holotype 34 I. craspedota. Scale bars: 1 mm.