Coeliccia mientrung, Kompier, Tom & Phan, Quoc Toan, 2017

Kompier, Tom & Phan, Quoc Toan, 2017, Coeliccia mientrung spec. nov. from Central Vietnam (Odonata: Platycnemididae), Zootaxa 4247 (2), pp. 131-140 : 131-136

1. Coeliccia mientrung spec. nov.

( Figs. 1 E–H, 2A–B, 3E–H, 4, 5)

Type specimens. Holotype ♂, Along QL 15, Quang Binh Province (appr. 17.492 N, 106.296 E), 23.VI.2016, TK leg. Allotype ♀, Bach Ma National Park, Thua Thien—Hue Province (16.195 N 107.861 E), 05.VIII.2016, TK leg. Paratypes 1♂, Bach Ma National Park , Thua Thien—Hue Province (16.195 N 107.861 E), 05.VIII.2016, TK leg. ; 1♂ 1♀, Thua Thien—Hue Province (16.084 N, 107.464 E), 21.VI.2016, TK leg. ; 7♂ 3♀, A Luoi Nature Reserve, Thua Thien—Hue Province, 18.IX.2015, QTP leg. ; 5♂ 4♀, Ba Na Nature Reserve , Da Nang city, 25.V.2015, QTP leg. ; 1♂ 1♀, Phong Nha—Ke Bang National Park , Quang Binh Province, 30.IV.2016, TK leg ; 1♂, Along QL 14, Thua Thien—Hue Province (appr. 16.064 N, 107.485 E), TK leg. ; 1♂, Along QL 14, Thua Thien—Hue Province (appr. 16.090 N, 107.464 E), 19.V.2016, TK leg. ; 1♂, Thua Thien—Hue Province (16.084 N, 107.464 E), 21.VI.2016, TK leg. ; 3♂, Along QL 15, Quang Binh Province (appr. 17.492 N, 106.296 E), 23.VI.2016, TK leg.

Etymology. The specific name mientrung , a noun in apposition, refers in Vietnamese to the area of central Vietnam where the species occurs.

Description of male holotype. Head ( Fig. 1 E). Labrum and postclypeus shiny black, anteclypeus bluish white, but ventral corners with grayish smudges. Genae and base of mandibles bluish white, the white narrowly extending over the postclypeus and almost connected, interrupted at center of postclypeus by matte black that covers dorsal surface of head, apart from two small white spots between base of antennae and posterior ocelli and two oblong postocular spots. Antennae black, but top of first and bottom of second segment white. Compound eyes three–colored in life, black dorsally, green at front, shading to blue at rear.

Prothorax ( Fig. 1 E). Matte black, with pair of whitish spots on middle lobe, propleuron largely whitish.

Synthorax ( Fig. 1 E). Mesepisternum black, but with an almost rectangular blue antehumeral stripe occupying half its length, starting from posterodorsal corner of mesinfraepisternum. Metepisternum and metepimeron light blue except for black line along metapleural suture, continued upward along antealar carina on metepisternum. Mesepimeron black with extensive blue marking in ventral half, contiguous with that on metepisternum ( Fig. 1 E). Mesinfraepisternum almost completely black, metinfraepisternum white with black margin along metepisternum. Legs. Grayish with black stripe over extensor surface of tibia and flexor surface of first pair of legs, and over flexor surface of femora; spines and claws dark. Coxae and trochanters white. Wings. Hyaline, 20 postnodal crossveins in forewing, 17 in hindwing. Pterostigma brown, covering one cell.

Abdomen. S1–2 black dorsally and white ventrally; S3–6 black dorsally and white ventrally, the white subapically extending upward to form a half–ring, more distinctly so on S5–6. S7–8 almost completely black. S9 black with yellow spot on posterior two-thirds of dorsum ( Fig. 1 H). S10 with yellow dorsal half and black ventral half ( Fig. 1 H). Anal appendages ( Fig. 1 F–G). Yellow, of typical Coeliccia type, cerci on distal half with triangular ventral expansion, directed somewhat inward and in lateral view appearing slightly rounded ( Fig. 1 F), its apex at proximal side and tipped with a black tooth. This ventral expansion runs to apex of cercus. Genital ligula ( Fig. 2 A– B). Apex of terminal segment of genital ligula has two flagella that lie parallel to it, originating laterally from apical corners, apex itself with flap-like fold, covering apical third of segment, that becomes progressively broader towards its distal margin.

Measurements (mm). Hindwing 28; abdomen including appendages 43.

Variation in paratype males. Occasionally blue stripe on mesepisternum not quite extending to middle of dorsum. In many males subapical ventral half–ring clear on S3–6, not just S5–6. Yellow on S9 sometimes restricted to posterior half of dorsum. 17–18 postnodal crossveins in forewing, 16 in hindwing.

Description of female allotype. Head ( Fig. 3 E–F). Labrum yellow, some brownish smudges along edges. Anteclypeus and mandibles greenish yellow, anteclypeus with a darker area on both sides. Postclypeus shiny black. Genae yellow, yellow extending above postclypeus but not quite connecting centrally. Remainder of dorsum of head matte black, apart from zigzag yellow lines running from frontal ocellus in front of lateral ocelli and reaching edge of eye and two small oblong postocular spots. Antennae blackish, but top of first and bottom of second segment white. Eyes three–colored in life, black dorsally, green at front, shading to blue at rear.

Prothorax ( Fig. 3 E, H). Pronotum black with pair of large yellow marks on middle lobe, propleuron pale yellow. Posterior pronotal lobe has a distinct rounded protrusion directed posteriorly on its posterior margin, with on either side a smaller flat earlike structure. Synthorax ( Fig. 3 E). Mesepisternum black with almost full length greenish-yellow antehumeral stripe ( Fig. 3 E). Mesepimeron largely black, but greenish yellow of metepisternum extending slightly onto ventral third. Mesinfraepisternum almost completely black. Metepisternum entirely yellow, but for thin black line over metapleural suture, dorsally connected to black of mesepimeron ( Fig. 3 E). Metepimeron and metinfraepisternum yellow. Legs. Yellowish with black stripe over extensor surface of tibia and also flexor surface of first pair of legs, and over flexor surface of femora; spines and claws dark. Coxae and trochanters pale yellow. Wings. Hyaline, 18 postnodal crossveins in forewing, 16 in hindwing. Pterostigma brown, covering one cell (2 cells in left forewing).

Abdomen. S1 yellow, but black dorsally. S2–7 black dorsally and yellow ventrally, some with hint of a subapical ventral half–ring. S8 with proximal two–thirds of dorsum black, extending not quite to venter, remainder yellow. S9 black with large yellow spot covering posterior two–thirds, laterally not reaching venter. S10 and cerci black. Ovipositor black with a small yellow spot at base and with yellow mark dorso-apically (for S8–10 see Fig. 3 G).

Measurements (mm). Hindwing 29; abdomen including appendages 40.

Variation in other paratype females. Postocular spots considerably larger. Prothorax with more black on middle pronotal lobe, almost encircling and thus isolating a large yellow spot on each half ( Fig. 3 E). Central protrusion of posterior pronotal lobe distinctly raised in lateral view and more triangular in anterior view ( Fig. 3 H). S9 dorsally completely yellow, the yellow thus continuous with that of posterior part of S8. 17 postnodal crossveins in forewing, 15 in hindwing.

Measurements (mm). Male. Hindwing 25–30; abdomen including appendages 39–46.

Female. Hindwing 28–30.5; abdomen including appendages 38.5–42.

Diagnosis. The males of C. mientrung are easily separated from all other Coeliccia species in Vietnam by the combination of blackish dorsum of the thorax with short blue antehumeral stripes and yellow S9–10 and appendages, apart from the similar C. pyriformis , from which it can consistently be separated by the following characteristics. In C. mientrung the yellow on S9–10 is restricted laterally and on S9 also dorsally ( Fig. 1 H). Contrary to the pattern of C. pyriformis ( Fig. 1 D), it does not extend to the anterior margin. Another character evident in live individuals concerns the color of the eyes. In C. mientrung the compound eyes are always three–colored ( Fig. 4 ), whereas in C. pyriformis they lack the green. Structurally the ventral expansion of the cercus extends to the apex of the cercus in C. mientrung ( Fig. 1 F), whereas in C. pyriformis it is more squared and ends well short of the apex ( Fig. 1 B), a difference easily noticeable in lateral view. Finally, the flagella at the apex of the terminal segment of the genital ligula of C. mientrung run more parallel to the terminal segment, and their apices are not hammerhead shaped ( Fig. 2 A–B), whereas in C. pyriformis , the flagella of the genital ligula run perpendicular to the terminal segment and their apices are hammerhead shaped ( Fig. 2 C–D). The apical fold of the genital ligula expands smoothly towards its distal margin in C. mientrung ( Fig. 2 A), whereas in C. pyriformis this fold expands laterally into a point near the distal margin ( Fig. 2 C). For differences between the males that are less consistent, see the discussion below. See Table 1 for a summary.

The females of C. mientrung can be separated from most known females of other species on the basis of the rounded protrusion at the middle of the posterior margin of the posterior pronotal lobe in combination with the thoracic pattern with a single antehumeral stripe on either side and the rounded yellow spots on the middle pronotal lobe. It can be separated less reliably from C. pyriformis and Indocnemis ambigua ( Asahina 1997) . The latter has only a minimal extension of the posterior pronotal lobe. The protrusion of C. pyriformis is squarish ( Fig. 3 D), where in C. mientrung it appears to vary from rounded to triangular ( Fig. 3 H), but never square. The only other consistent difference from female C. pyriformis is the color of the labrum. In all our specimens of C. pyriformis the labrum is black ( Fig. 3 B), but in those of C. mientrung it is yellow or largely yellow ( Fig. 3 F). A combination of characters further supports identification. See the discussion and Table 2.

Figures

FIGURE 1. Comparison of male C. pyriformis (A – D) and C. mientrung (E – H): head and thorax (A, E), caudal appendages in lateral view (B, F), caudal appendages in dorsal view (C, G), abdomen tip (D, H).

FIGURE 2. Genital ligula of C. mientrung (A – B) and C. pyriformis (C – D): ventral view (A, C), lateral view (B, D).

FIGURE 3. Comparison of female C. pyriformis (A – D) and C. mientrung (paratype Thua Thien—Hue Province 21. VI. 2016) (E – H): head and thorax (A, E), head in anterior view (B, F), abdomen tip (C, G), posterior pronotal lobe in anterior view (D, H).

FIGURE 4. Male C. mientrung in nature, 5. VIII. 2016, Bach Ma National Park, Thua Thien—Hue Prov. Note three – colored eyes, white spots in prothorax, short truncated antehumeral stripes and limited yellow on S 9.