Coeliccia natgeo, Phan & Ngo & Toan & Tuan, 2020

Phan, Quoc Toan, Ngo, Quoc Phu, Toan, Thai Canh & Tuan, Vo Anh, 2020, Description of Coeliccia natgeo sp. nov. from Central Vietnam with keys to the males and females of the hayashii-group (Odonata: Zygoptera: Platycnemididae), Zootaxa 4896 (1), pp. 96-104 : 97-102

Coeliccia natgeo sp. nov.

( Figures 2–18 , 20, 21 )

Holotype. ³, Khe Nhop (18.2708 N, 105.3431 E; alt. 510 m), Vu Quang NP, Kim Quang Commune, Vu Quang District , Ha Tinh Prov., 3.vi.2020, Q. T. Phan leg.

Paratypes. 2 ³³, same data as the holotype; 2 ³³, Khe Tron Cua (18.2782 N, 105.3725 E, alt. 95 m), Vu Quang NP, Kim Quang Commune, Vu Quang District , Ha Tinh Prov., 30.v.2020, Q. T. Phan & Q.P. Ngo leg. ; 4 ³³, 1 ♀ (caught in tandem), Vu Quang NP, Son Kim 2 Commune (18.4387 N, 105.2146 E, alt. 127 m), Huong Son District , Ha Tinh Prov., 05.vii.2018, Q. T. Phan leg. ; 4 ³³, Khe Kem (18.9729 N, 104.8168 E, alt. 273 m), Pu Mat NP, Luc Gia Commune, Con Cuong District , Nghe An Prov., 14.v.2019, Q. T. Phan leg.

Type specimen deposition. All type specimens of the new species are deposited in the Zoological Collection of Duy Tan University , Da Nang City, Vietnam . Two males from Son Kim 2 will be placed in the private collection of Dr. Rosser William Garrison, Sacramento, USA .

Etymology. The specific name of the new species, natgeo is a partial abbreviation of the National Geographic Society, in appreciation of their financial support to the authors. The name is to be treated as an indeclinable noun.

Other material confirmed by field observations. 1 ³, Khe Sai (18.3862 N, 105.3055 E, alt. 69 m), Vu Quang NP, Son Kim 1 Commune, Huong Son District, Ha Tinh Prov., 23.vii.2020, Q.T. Phan; 1 ♀ (immature), Son Kim 2 Commune (18.4387 N, 105.2146 E, alt. 127 m), Huong Son District , Ha Tinh Prov., 05.vii.2018, Q. T. Phan .

Description of holotype. Head ( Figs 4, 5 ). Labrum and postclypeus black; anteclypeus black with a median blue spot; genae and base of mandibles largely blue, this pattern extends inward above the postclypeus, but inter-rupted in the middle; antennae black, first segment yellow above; epicranium matte black apart from two tiny yel-low spots adjacent to posterior ocelli and two small narrow yellow postocular spots; compound eyes tricolored in life, with top half black and bottom half greenish turning blue posteriorly ( Figs 14, 15 ).

Thorax ( Fig. 8 ). Pronotal lobes entirely black dusted with pruinosity; propleuron pale yellow; mesepisternum and mesepimeron black, metepisternum and metepimeron yellow except for narrow metepleural black stripe extending almost to the spiracle; mesinfraepisternum black above, yellow below. Legs ( Fig. 8 ). Coxae and trochanters pale yellow, femora and tibiae pale grayish with black lines along extensor and flexor surfaces, armature dark brown.

Wings. Hyaline, 19 Px in FW and 17–18 in HW; Pt dark brown, surmounting 1.5 cells.

Abdomen ( Figs 2 , 8 ). S1 largely yellow, black dorsally and along posterior margin; S2 black in upper half, yel-low below; S3–6 black above and yellow below with blackish nodes; S7–8 black, narrowly yellow below; anterior half of S9 black, posterior half yellow; S10 entirely yellow.

Anal appendages yellow. In lateral view ( Fig. 10 ) cercus short, robust, with apex smoothly rounded with a ventral expansion tipped with a black tooth; paraproct longer than cercus, enlarged basally thereafter curvilinear dorsally with medially directed tip ending in a black tooth. In dorsal view ( Fig. 11 ) cercus expanded mediobasally gradually narrowing apically.

Genital ligula ( Fig. 12 ) with terminal segment separated at base into a pair of long, acute tipped flagella.

Measurements (in mm). HW 27; abdomen including appendages 44.

Variation in paratype males. Four males from Son Kim 2 Commune are smaller than the holotype: Abdomen (including appendages) 37–38 mm, HW 25 mm; the abdomen of four males from Son Kim 2 Commune and a male from Khe Kem differ from the holotype by having S9 mostly yellow.

Description of paratype female. Head ( Figs 6, 7 ). Labrum black; anteclypeus yellow with pair of widely separated brown spots on lower margin; postclypeus shiny black; genae and base of mandibles yellow, this pattern extending inward above postclypeus; remainder of frons matte black; antennae black, top of scape yellow; epicra-nium matte black with a large transverse yellowish stripe narrowly interrupted medially originating at compound eye margin and extending to just adjacent to the median ocellus, bifurcated just before level of lateral ocellus with one arm extending to behind median ocellus, the other reaching the lateral ocellus ( Fig. 7 ). Two large transverse yellowish postocular spots.

Thorax ( Figs 9 , 13, 14 ). Anterior and posterior pronotal lobes black, middle pronotal lobe black centrally, yellow laterally ( Fig. 13 ); posterior pronotal lobe with central part very small, slightly raised upward, appearing as a small projection in lateral view ( Fig. 14 ), with two black distinct lapels; synthorax as in holotype apart from yellow antehumeral stripes ( Fig. 9 ). Legs as in male.

Wings. Hyaline, 19 Px in FW and 17–18 in HW. Pt brown, surmounting 1.5 cells.

Abdomen ( Figs 3 , 15, 16 ). S1–7 as male; S8–9 black with yellowish apical markings, deeply divided dorsally ( Figs 15, 16 ); S10 entirely black. Ovipositor yellowish with a central black spot and black ventral half.

Anal appendages ( Figs 15, 16 ). Cerci dark brown, almost as long as S10.

Measurements (in mm). HW 25; abdomen including appendages 37.

Differential diagnosis. Within the hayashii -group (and this is also true for C. yunnanensis ), the fully mature males of C. duytan , C. mattii , C. schorri and C. lecongcoi lack antehumeral stripes or spots. Coeliccia schorri has extensive blue marking on the terminal abdominal segments and pruinose markings on the synthorax ( Phan & To 2019: Fig. 8 ) and the synthorax of C. mattii is largely covered by pruinosity ( Phan & Kompier 2016: 3 C). Male structural characters of C. diomedea are very similar to C. natgeo apart from always present antehumeral markings, although it displays some variation in the size of its antehumeral spots ( Kompier et al. 2020). All mature males collected (or observed) in the range of C. natgeo do not show antehumeral markings.

With the other two species, C. natgeo shares the yellow abdomen tip and appendages, but it differs from C. duytan and C. lecongcoi as follows: (1) synthorax lacking pruinosity ( Figs 8 , 17, 18 ) (large lateral pruinose areas and small dorsal spots, Phan 2019: Figs 9–10 ); (2) S9 of C. natgeo largely yellow ( Figs 10, 11 ) whereas S9 almost black in C. duytan ( Phan 2017: Fig. 2 a-b) and C. lecongcoi (Phan 2019: Figs 5, 6 ). The short and robust cerci and the apically pointed flagella of the genital ligula of C. natgeo resemble those of C. duytan and C. lecongcoi .

The female of C. natgeo differs from all other species in the hayashii -group (and probably from most other Coeliccia species) by the reduced central part of the posterior pronotal lobe of the prothorax ( Figs 20, 21 ). In C. mattii the central part of the posterior pronotal lobe is much larger and rearward directed, not at all similar to C. natgeo ( Fig. 22 ). The central part of the posterior pronotal lobe of the females of C. coronata , C. diomedea , C. duytan , C. hayashii and C. lecongcoi has a well-developed triangular structures with lateral extensions ( Figs 23–32 ). The female of C. schorri differs from all other members of the hayashii -group in that the central part of the posterior pronotal lobe is a long erect horn ( Fig. 19 ).

Habitat and ecology. Unlike most species of Coeliccia , C. natgeo was found in dry areas, about 5–10 m from the edge of small, densely vegetated streams. It is probably a low-density species since it was seldom encountered during our field trips. Within Vu Quang NP, C. natgeo occurs with C. pyriformis Laidlaw, 1932 and other shade dwelling such as Drepanosticta emtrai Dow, Kompier & Phan, 2019 ; Protosticta pseudocuriosa Phan & Kom-pier, 2016; Devadatta cyanocephala Hämäläinen, Sasamoto & Karube, 2006 ; Burmagiolestes melanothorax (Selys, 1891), Agriomorpha fusca May, 1933 and Prodasineura lancastrei Phan & Ngo, 2020 . In Pu Mat NP, C. pyriformis ; C. scutellum Laidlaw, 1932 ; B. melanothorax, A. fusca and D. emtrai were found with C. natgeo .

Figures

FIGURES 2–3. Habitus of Coeliccia natgeo sp. nov. (2) holotype ³ & (3) paratype ♀.

FIGURES 4–7. Head of Coeliccia natgeo sp. nov. in dorsal & frontal view. (4, 5), holotype ³ & (6, 7), paratype ♀.

FIGURES 8–9. Head and thorax of Coeliccia natgeo sp. nov., lateral view. (8), holotype ³ & (9), paratype ♀.

FIGURES 10–16. Structural characters of Coeliccia natgeo sp. nov. [10–12] holotype ³ & [13–16], paratype ♀. (10), S9–10 & anal appendages, lateral view; (11), S9–10 & anal appendages, dorsal view; (12), genital ligula, ventral view; (13, 14), pro- thorax; (15, 16), abdominal tip.

FIGURES 17–18. Males of Coeliccia natgeo sp. nov. in nature. (17), Khe Nhop; (18), Khe Kem. All photos are taken by Q.T. Phan.

FIGURES 19–32. Posterior pronotal prothoracic lobes of females of the hayashii-group, ♀. (19), C. schorri (rearranged from Phan & To 2019), lateral view; (20, 21), C. natgeo, dorsal & lateral view; (22), C. mattii (rearranged from Phan & Kompier 2016), oblique dorsal view; (23, 24), C. coronata, Chu Yang Sin, dorsal & lateral view; (25, 26), C. duytan, Chu Mom Ray, dorsal & lateral view; (27, 28), C. hayashii, Ko Roong, dorsal & lateral view; (29, 30), C. diomedea, Dak Glei, dorsal & lateral view; (31, 32), C. lecongcoi, Ngoc Linh, dorsal & lateral view.