Planaeschna maculifrons, Zhang, Hao-Miao & Cai, Qing-Hua, 2013

Zhang, Hao-Miao & Cai, Qing-Hua, 2013, Discovery of four new species of the genus Planaeschna from Southwestern China (Odonata: Anisoptera: Aeshnidae), Zootaxa 3741 (2), pp. 254-264 : 257-261

Planaeschna maculifrons sp. nov.

Figs. 10–15

Material examined. Holotype male, Mt. Emeishan, Wannian Temple (29°35'N, 103°23'E), altitude 880 m, Emeishan City, Sichuan Province, China, Haomiao Zhang leg., 20. VIII. 2007.

Etymology. The name maculifrons means ‘spot on frons’, referring to the unique color pattern of the frons, which has a large triangular black spot seen in frontal view; this is a character unique to the new species.

Diagnosis. Large sized in the genus, body mainly black with green maculations; separated from its closest congeners by details of head marking, yellow patches on legs and structure of male appendages.

Holotype Male: Head yellowish green with black markings, eyes bluish green in living specimen ( Figs. 10– 11 ). Labium brownish yellow, labrum yellow with lower margin black. Anteclypeus entirely dark brown, postclypeus yellow. Frons mainly yellowish green frontally, with a large triangular black spot, dark brown dorsally without “T” mark.

Prothorax black. Synthorax black with greenish yellow markings as follows ( Fig. 10 ): mesepisternum with antehumeral stripe, slightly bent and tapering ventrad, and small rounded spot in posterior lower corner; carina entirely black; mesepimeron with broad stripe; metepisternum with triangular spot near upper margin, olive-shaped spot at middle and very small spot under metastigma; metepimeron with broad marking; mesokatepisternum and metakatepisternum each with yellow patch. Legs mainly black, basal 2/3 of femur in fore and mid leg brownish yellow, hind femur with brownish yellow patch in middle ( Fig. 10 ).

Wings hyaline. Triangle 6-celled in fore wings and 4-celled in hind wings, anal loop 9- or 10-celled, anal triangle 4-celled. Pterostigma blackish brown, 2.5 mm in length. Nodal index: 16: 23: 23: 18 / 19: 16: 16: 17.

Abdomen black with greenish yellow markings as follows ( Fig. 10 ): S1 with large spot laterally; S2 with triangular AD spot, pair of triangular MD spots, pair of irregular PD spots and very fine longitudinal line posteriorly, side of S2 with large AL spot covering auricle and two separated PL spots; S3 with triangular AD spot, paired triangular MD spots, paired semicircular PD spots and large AL spots, the PL spots reduced; S4–8 with paired triangular MD spots and olive-shaped PD spots; S9–10 with paired olive-shaped PD spots. S10 with very short pyramidal process dorsally.

Anal appendages black. Superior appendages in lateral view suddenly expanded from basal 1/4, expanding toward apex and broadest at basal 2/3 ( Fig. 12 ); in dorsal view, expanded at apical 1/2, with small apical spine ( Fig. 13 ). Inferior appendage slightly longer than half length of cerci, slightly bent with apical small tuberculate process in lateral view.

Vesica spermalis brown and black ( Figs. 14–15 ): Vesicle hollow anteriorly; 2nd segment strongly bending with stout projection dorsally; 3rd segment almost straight, tapered distally; 4th segment with two lobes, in ventral view each with protruding ear-shaped lobe and tapered apex, in lateral view median bulge with two obvious “camel humps.”

Female unknown.

Measurements (mm). Holotype: total length 72.0, abdomen (including anal appendages) 55.5, hind wing 47.0.

Distribution. China (Sichuan).

Notes on biology. The holotype was collected near a very shady stream in late afternoon (18:00h), when it was foraging at rather low speed about 1m above the ground. The stream is about 0.5m wide and slightly polluted by the village upstream. It is home to Megalestes distans Needham, 1930 , Chlorogomphus tunti Needham, 1930 Chlorogomphus nasutus Needham, 1930 , and Anotogaster kuchenbeiseri (Förster, 1899) .

Discussion. Planaeschna maculifrons is very similar to P. robusta described above, but it can be distinguished by the combination of characters both in body maculation and structure of anal appendages. The unique black, triangular spot on the frons is one of its most outstanding characters, not seen in congeners, and the large yellow patches on S10 also separate it from P. robusta . In lateral view, the superior appendagesi of P. ro b u s t a are broadest at basal 1/4 but at basal 2/ 3 in P. maculifrons . P. skiaperipola is similar in this aspect, possessing superior appendages broadest at about basal 1/3, but P. maculifrons is different from it by body maculation and vesica spermalis structure, with ear-lobes on the 4th segment in ventral view that are missing in P. skiaperipola . In dorsal view, the superior appendages of P. cucphuongensis Karube, 1999 , are similar. P. maculifrons is easily distinguished from P. cucphuongensis by the combination of body markings and structure of superior appendages in lateral view, broadest at basal 2/ 3 in P. maculifrons but at midpoint in P. cucphuongensis .

Planaeschna caudispina sp. nov. Figs. 16–24

Material examined. Holotype male, Mt. Qingchengshan (30°54'N, 103°28'E), altitude 1100m, Dujiangyan City, Sichuan Province, China, Haomiao Zhang leg., 30. VIII. 2007; paratypes: 2 ♂ 2 ♀, same data as holotype.

Etymology. The name caudispina means ‘tail with spine’, to emphasize the dorsal pyramidal process on S10 and the very small spine on the distal margin of that segment in this new species.

Diagnosis. Moderately large for the genus, body mainly black with greenish yellow maculations; separated from its closest congeners by face without black marking on anterior surface of frons, very well-developed thoracic maculation and structure of male appendages.

Holotype Male: Head yellow with black markings, eyes bluish green in living specimen ( Figs. 16–17 ). Labium brownish yellow, labrum yellow with a median black spot in lower margin. Anteclypeus entirely dark brown, postclypeus yellow. Anterior surface of frons mainly yellow, with obscure black “T” mark dorsally, upper margin of frons medially protruding upward. Occiput black, fringed with setae.

Prothorax black. Synthorax black with greenish yellow markings as follows ( Fig. 16 ): mesepisternum with antehumeral stripe slightly bent and tapering ventrad, with small rounded spot in posterior lower corner; carina with brown stripe; mesepimeron with broad stripe, posterior lower corner with linear stripe extending to middle leg; metepisternum with linear stripe expanded toward upper margin, and rounded spot under metastigma; metepimeron with broad marking; mesokatepisternum and metakatepisternum each with yellow spot. Legs mainly black, coxae yellow posteriorly, inner margin of femur in fore and mid legs with yellow stripes ( Fig. 16 ).

Wings hyaline. Triangle 3-celled in both wings, anal loop 6- or 7-celled, anal triangle 3-celled. Pterostigma blackish brown, 2.5 mm in length. Nodal index: 13: 22: 22: 14 / 15: 15: 16: 17.

Abdomen black with greenish yellow markings as follows ( Fig. 16 ): S1 with very small AD spot and transverse “U” mark laterally; S2 with drop-shaped AD spot, pair of linear MD spots, pair of triangular PD spots and very fine longitudinal line posteriorly; side of S2 with large AL spot covering auricle and two PL spots connecting with PD spots; S3 with triangular AD spot, paired linear MD spots, paired semicircular PD spots that connect with the small PL spots, and large AL spots; S4–7 with paired linear MD spots and semicircular PD spots; S8–9 with very small triangular PD spots. S10 black dorsally and yellow ventrally, with pyramidal process dorsally, not developed into a long spine ( Fig. 20 ). Distal margin of S10 with pair of very small spines close to base of cerci, visible in lateral view ( Fig. 20 ).

Anal appendages black. Superior appendages gradually expanded toward apex in lateral view and broadest at apical 2/5 ( Fig. 20 ); in dorsal view, expanded at apical 2/3, with small apical spine ( Fig. 21 ). Inferior appendage about 1/2 length of cerci, slightly bent with apical small tuberculate process in lateral view ( Fig. 20 ).

Vesica spermalis brown and black ( Figs. 22–23 ): Vesicle hollow anteriorly; 2nd segment strongly bending with stout dorsal projection; 3rd segment almost straight and not obviously tapered; 4th segment with two lobes and lacking protruding ear-shaped lobes, in ventral view distal half lobes adjoining, expanded and rounded, while hind half lobes divided, and hind corner angled; in lateral view, median bulge erected to lower half of 3rd segment.

Paratype female: Head brownish yellow with black markings, eyes green with blue patch in living specimen ( Figs. 18–19 ). Labium brownish yellow, labrum yellow with a median black spot in lower margin. Anteclypeus entirely dark brown, postclypeus yellow. Frons mainly yellow, with pale brown inverted “V” frontally and very obscure black “T” mark dorsally, upper margin of frons medially protruding upwards. Occiput black, fringed with setae.

Thoracic color pattern very similar to male, but with more developed antehumeral stripe. Legs with well developed yellow patches in all legs ( Fig. 18 ).

Wings hyaline, slightly tinted with smoky brown. Triangle 4-celled in both wings, anal loop 9-celled. Pterostigma blackish brown, 2.5 mm in length. Nodal index: 14: 21: 23: 15 / 16: 18: 15: 16.

Abdomen black with yellow stripes ( Fig. 18 ): S1 with a large spot dorsally, and rectangular spots laterally; S2 with large AD spot, paired MD spots that connect with lateral stripes and large triangular PD spot, side of S2 with very broad stripe; S3–4 with AD spot, reduced on S4; S3–7 with paired linear MD spots; S3–9 with PD spots, reduced on S7–9; S3–8 with AL spots, S3–6 with PL spots; tergite of S10 ventrolaterally produced. Ovipositor black and brown, reaching end of S10. Superior appendages same length as S10 ( Fig. 24 ).

Measurements (mm). Holotype: total length 70.0, abdomen (including anal appendages) 54.0, hind wing 44.5; paratype males: total length 67.5–71.0, abdomen (including anal appendages) 52.0–54.0, hind wing 43.0– 45.5; paratype females: total length 65.0–68.0; abdomen (including anal appendages) 49.0–53.0, hind wing 45.5– 47.0.

Variation in paratype male. A paratype male has the frons slightly tinted with brown frontally as in female.

Distribution. China (Sichuan).

Notes on biology. The habitats of the new species is semi-shaded montane streams, about 0.5m wide. All the specimens collected were from 16:00h to 18:30h, when males were observed to fly very fast along the stream, usually less than 0.5m above water. Females foraged in the forest near the streams at lower speed than the males. Species co-occuring at the type locality were Caliphaea consimilis McLachlan, 1894 , and Matrona oreades Hämäläinen, Yu & Zhang, 2011 .

Discussion. This new species possesses very well developed yellow markings on the thorax and abdomen, and its unmarked face is different from all other Chinese Planaeschna , which always have black spots on the frons. The Chinese name of Planaeschna , called “Heieting” means “aeshnid with black spots on frons”, so this new species is an exception. Among all the known species from mainland China and Taiwan, P. taiwana , P. haui and P. skiaperipola possess a linear stripe on the metepisternum, but P. caudispina can be separated from them by the color pattern of the face and structure of appendages. Also P. caudispina has a more developed pyramidal process on S10 and very small spine on the distal margin of the segment. Another species with pyramidal process on S10 is P. shanxiensis , the female of which also possesses short superior appendages. The structure of appendages of P. caudispina is very similar to P. maolanensis , known from the neighbouring Guizhou province. P. maolanensis is a smaller species with brown face, the frons is slightly tinted with black, the mesepisternum lacks the small rounded spots in the posterior lower corner and the metepisternum has the linear stripe not expanded as seen in P. caudispina . From S 1 in lateral view P. maolanensis is different from P. caudispina by two small yellow spots. The vesica spermalis of P. maolanensis was not illustrated in the description and female is still unknown. Futher comparison between the two species is needed.

Figures

FIGURES 10 – 15. Planaeschna maculifrons sp. nov., holotype male: (10) body in lateral view; (11) head in frontal view; (12) appendages in lateral view; (13) appendages in dorsal view; (14) vesica spermalis in lateral view; (15) vesica spermalisin ventral view.

FIGURES 16 – 24. Planaeschna caudispina sp. nov., holotype male (16 – 17, 20 – 23) and paratype female (18 – 19, 24): (16) body in lateral view; (17) head in frontal view; (18) head in frontal view; (19) body in lateral view; (20) appendages in lateral view; (21) appendages in dorsal view; (22) vesica spermalisin lateral view; (23) vesica spermalisin ventral view; (24) ovipositor.