Protohermes subparcus Liu and Yang

Liu, Xingyue, Hayashi, Fumio & Yang, Ding, 2009, Systematics of the Protohermes parcus species group (Megaloptera: Corydalidae), with notes on its phylogeny and biogeography, Journal of Natural History 43 (5 - 6), pp. 355-372 : 367-371

Protohermes subparcus Liu and Yang

( Figures 5 , 33–38 )

Protohermes subparcus Liu and Yang, 2006a: 485 . Type locality: Yunnan (Weixi).

Diagnosis

Head yellow without any markings; pronotum with posterior halves of black vittae narrowed and longitudinally separated; male tenth tergum as long as ninth tergum, with apex slightly widened and rounded; male ninth sternum with oblique lateral margins and a deeply V-shaped posterior incision.

Material examined

Holotype: male, CHINA, Yunnan, Baijixun, Xiaoweixi , 21 ° 279N, 90 ° 079E, 1900 m, 4/ 6 June 2004, leg. H. Huang ( CAU) . Paratypes: three males, same data as holotype ( CAU) . One male, CHINA, Yunnan, Baijixun, Xiaoweixi , 1800 m, 5/ 12 June 2004, leg. H. Huang ( CAU) ; one male, CHINA, Yunnan, Gongshan, Pulahe River , 27 ° 439N, 98 ° 399E, 1500 m, 19 May 2007, leg. X.Y. Liu ( CAU) .

Male

Body length 28–33 mm; forewing length 41–43 mm, hindwing length 36–39 mm.

Head. Yellow, without any markings; post-ocular spine short and blunt. Compound eyes brown; ocelli pale yellow, medially margined black. Antennae black, with scape and pedicel yellowish brown. Mouthparts pale yellowish brown; mandibles with apices blackish brown, galea and apical two segments of maxillary palpi blackish brown.

Prothorax. Pale yellow; pronotum with a pair of black vittae on lateral margins, anterior portions of vittae slightly curved laterally, posterior portions of vittae narrowed and longitudinally separated into two slender vittae. Meso- and metathorax pale yellow, with anterolateral corners brownish. Thoracic pilosity pale yellow, much longer on meso- and metathorax. Legs pale yellow with yellowish short dense setae; wide apices of tibiae brownish, tarsi brownish ventrally, tarsal claws reddish brown. Wings hyaline, immaculate, pale grayish brown except for anal areas; veins blackish brown, costal and subcostal veins pale yellowish brown, cubital and apical half of anal veins pale yellow. Rs 9- to 10-branched, last branch bifurcate or trifurcate; 9–13 crossveins between R 1 and Rs; M 1+2 four-branched, M 3+4 twobranched; 1A three-branched.

Abdomen. Blackish brown with venter pale yellow. Ninth tergum ( Figure 34 ) broad, nearly hexagonal, with a V-shaped posterior incision. Ninth sternum ( Figure 35 ) broad, with oblique lateral margins; posterior margin with a deep, V-shaped median incision; median portion with a deep longitudinal incision. Ninth gonostylus ( Figure 36 ) unguiform, feebly curved inwards, sometimes with a small tubercle at tip. Tenth tergum ( Figures 34, 37 ) flattened, subquadrate, as long as ninth tergum, longer than wide, ventrally incised except margins; apex somewhat widened and rounded. Tenth sternum ( Figure 38 ) extremely small, with a dorsomedial process well developed and longer than lateral lobes; lateral lobes shortly subuliform.

Female

Unknown.

Distribution

China (Yunnan).

Remarks

See the remarks of P. flavinervus and P. parcus .

Phylogeny

The exhaustive search resulted in a single most parsimonious tree (length513, consistency index (CI)50.8462, retention index (RI)50.8667) ( Figure 39 ). The monophyly of the P. parcus group was supported by the hexagonal male ninth tergum (character 2:1) and the male tenth tergum not pointed posteriorly (character 6:1). Protohermes pennyi emerged as the sister species to the remaining ingroup species, indicating a relatively early divergence from the P. parcus group. The clade of P. congruens , P. flavinervus , P. parcus , and P. subparcus is supported by the immaculate head (character 1:1) and the male tenth tergum straightly directed posteriorly (character 5:1). Within this clade, P. flavinervus , P. parcus , and P. subparcus were grouped by the male ninth sternum medially with a deep longitudinal incision (character 3:1), the subuliform lateral lobes of the male tenth sternum (character 7:1), and the female eighth sternum with the posterior margin medially incised (character 10:1). Thus, P. parcus and P. subparcus were assigned as a sister pair, which is consistent with the result of Liu and Yang (2006a), by the distally sinuate male ninth gonostylus (character 4:1) and the well-developed dorsomedial process of the male tenth sternum (character 8:1).

Biogeography

Currently, the species of the P. parcus group are disjunctly distributed in south-west China and Nepal ( Figure 40 ). Protohermes pennyi occurs in the northern part of central Nepal, which is near the southern side of Mt Himalaya. Three species, P. flavinervus , P. parcus , and P. subparcus , are distributed in west and north-west Yunnan along Mt Gaoligong, which is located at the boundary of China and Myanmar and close to the upper Salween River. Mt Gaoligong is divided into two parts from north to south at approximately 26 ° 209N. The northern part has many high mountains with elevation up to 4500 m and has the mid temperate climate, while the southern part has most mountains with elevation lower than 3500 m and has the subtropical climate ( Li and Long 1999). Protohermes parcus is distributed only in the southern part of the Mt Gaoligong, showing its preference to the warmer climate. However, P. flavinervus and P. subparcus inhabit the northern part. The distribution area of P. flavinervus is restricted to Dulongjiang, which is at the western side of the Mt Gaoligong and close to northern Myanmar. The range of P. subparcus extends easterly from the eastern side of Mt Gaoligong to Mt Bilo, which is near the upper Mekong River.

The centre of origin of the extant Asian Corydalidae was proposed in south-west China and north-east Indian subcontinent ( Liu and Yang 2006a, 2006c; Liu et al. 2007a). Thus, the numerous high mountains formed by the collision between the Indian subcontinent and the Laurasia during Eocene stimulated the speciation of the Asian Corydalidae . The range of the P. parcus group falls within the assumed centre of origin. Based on the present phylogeny of the P. parcus group, P. pennyi , the basal group member, is distributed in Nepal. Hence, the earlier divergence within the P. parcus group might have happened in Nepal due to the elevation of Himalaya. The Chinese fauna might have been generated subsequently by the formation of Mt Gaoligong.

Besides Nepal and Yunnan, the mountainous areas in Bhutan, north-east India, and north Myanmar probably harbour the species of the P. parcus group because of the similar habitat. So, the current disjunct distribution of the P. parcus group might be due to insufficient sampling in the areas between China and Nepal. Intensive sampling in these areas might improve the knowledge of the P. parcus group in the future.

Figures

Figure 39. Most parsimonious tree for all species of the P. parcus species group. Only unambiguous characters are shown. Shaded squares represent apomorphic characters, open squares represent parallelisms. Bremer’s decay indices are shown at nodes.

Figure 40. Distribution map for all species of the P. parcus species group. (&) P. flavinervus sp. nov; (•) P. parcus Yang and Yang; (w) P. pennyi sp. nov; (m) P. subparcus Liu and Yang; (circled question mark) P. congruens sp. nov., but without exact geographical data.

Figures 1–5. Habitus photographs of the species in P. parcus group. (1) Protohermes congruens sp. nov., male holotype; (2) Protohermes flavinervus sp. nov., male holotype; (3) Protohermes parcus Yang and Yang, male holotype; (4) Protohermes pennyi sp. nov., male holotype; (5) Protohermes subparcus Liu and Yang, male holotype.

Figures 33–38. Protohermes subparcus Liu and Yang. (33) Male head and prothorax, dorsal; (34) male genitalia, dorsal view; (35) male ninth sternum, ventral view; (36) male ninth gonostylus, ventral view; (37) male tenth tergum, ventral view; (38) male tenth sternum, ventral view.Note: Scale bars: 1 mm.