Sangabasis braulitae ( Villanueva, 2005 )

Villanueva, R. J. T. & Dow, R. A., 2014, Review of the Philippine taxa formerly assigned to the genus Amphicnemis Selys, II. Genus Sangabasis with descriptions of eight new species (Odonata: Coenagrionidae), Zootaxa 3815 (1), pp. 1-28 : 3-5

Sangabasis braulitae ( Villanueva, 2005)

( Figs. 1 , 8, 9 , 27 , 41 , 53 , 65 )

Amphicnemis braulitae Villanueva 2005: 77 –81, Figs. 1–4 (original description both sexes, Camiguin, Philippines). Amphicnemis sp. ( cf. dentifer );— Hämäläinen & Müller (1997: 259, 278: note 31, part, population from Homonhon). Sangabasis braulitae (Villanueva) ;—Villanueva (2012: 594–595, Figs 3, 4 , 6 , 13 ).

Type material. Holotype: ♂, Philippines, Camiguin, Guinsiliban, Lilob, 30 iv 2003, leg. RJTV, card labels: “ Lilob, Guinsiliban, Camiguin Is., male, perched on twig, 30.iv.2003, R.J. Villanueva”, in RMNH. Paratypes: 2 ♀, location as holotype, in RMNH; 2 ♂, location as holotype.

Other material (all from Philippines, Eastern Samar Province, Homonhon Island, all in RMNH). ♂, 3 ♀, Magallanes Point, 24 v 1988, leg. R.A. Müller; ♂, same location 1 iv 1988, leg. W. Catal; 18 ♂, 6 ♀, no specific location, 1–9 i 1988, leg. T. Borromeo; 23 ♂, 7 ♀, Bitaogan, 12 v 1988, leg. R.A. Müller; 15 ♂, 8 ♀, same location, iv 1988, leg. W. Catal; ♂, Culasi, 13 v 1988, leg. R.A. Müller.

Description of holotype male. Head: Labium pale, mandible bases brown with broad pale border except adjacent to labrum. Labrum shiny black except for yellow distal third. Genae pale, this colour continued to eye margin and narrowly along eye margin to level of antennal sockets. Anteclypeus pale blue adjacent to labrum, black above. Postclypeus black. Frons black, with distinct ridge, anterior face with paired transverse yellow streaks separated centrally. Vertex black with metallic reflection except for pale vertical streaks on antennal sockets. Rest of antennae brown. Remainder of head dark metallic green. A distinct rounded tubercle situated anteriorly beside the eye margin in the post ocular area.

Thorax: Prothorax dark metallic green except for pale transverse streak on crest of anterior lobe, lower part of propleuron, and brownish tips of horns of posterior pronotal lobe. Posterior pronotal lobe with shelf ( Fig. 8 ) rounded centrally with corners produced as short dorsolaterally directed spurs. Horns of posterior pronotal lobe long, rearward directed, broadly flat at base then tapered to bluntly pointed tip ( Figs 1 , 8 ). Synthorax ( Fig. 27 ) with dorsal carina equipped with short blunt process arising at anterior 1/4 of its length.

Mesinfraepisternum metallic green with irregular pale borders. Mesepisternum metallic green, mesepimeron metallic green, this becoming indistinct towards wing bases, and becoming pale above interpleural suture after first third, black at antealar carina. Metepisternum pale except for subtriangular area arising from upper part of antealar carina. Metepimeron pale except for black ovoid mark in distal part of metapleural suture. Legs pale with dark spines, blackish streaks on extensor surfaces and dark markings around joint of femur and tibia. Tarsi without denticle. Wings hyaline with dark brown veins. Arc at level of Ax2, Ac near Ax2, petiolation ceases before the level of Arc. R4 arising slightly proximal to subnodus; IR3 distal to subnodus. 12 Px in each wing. Pt brown, rectangular, costal a little shorter than subcostal side.

Abdomen: S1 pale with shiny apical–dorsal black patch. S2 black dorsum, pale below; S3–7 dark brown above, becoming black apically, with pale basal annulus; pale lower laterally. S8–10 largely black with pale lower lateral marks. Cerci whitish with blackened tips, more than twice length of S10. Upper branch of cerci with fork at ca 1/3 length ( Fig. 53 ). In lateral view cerci as shown in Fig. 41 , with blunt ventrally directed interior tooth at tip, inner apical surface somewhat concave. Spur slightly shorter than distance from S10 to fork, well visible in lateral view, bearing short setae dorsally (not shown in Fig. 53 ). Lower branch of cerci vermiform, white, clearly visible in lateral view ( Fig. 41 ), hugging ventral surface of upper branch and extending to base of spur of upper branch in lateral view. Paraprocts typical for genus.

Measurements (mm): abdomen including cerci 35, Hw 21.

Variation in males: Horns of posterior pronotal lobe sometimes slightly bent outward ( Fig. 9 ) and relatively shorter than in holotype. In some specimens corners of shelf of posterior pronotal lobe relatively shorter. Concavity in inner surface of apical part of upper branch of cercus broader in some specimens.

Measurements (mm): abdomen including cerci 29–39, Hw 21–23.

Female. Similar to male except for small details of colouration of head, abdomen with S8 with more extensive yellow on sides and black on S9 almost restricted to dorsum.

Measurements (mm): abdomen 30–36; Hw 20–23.

Diagnosis. Amongst the species of Sangabasis with the rudimentary lower branch of the cercus present, S. braulitae can be recognised by the combination of shelf of posterior pronotal lobe with corners produced as upward-directed spurs, dorsal carina of synthorax with short tubercle, and lower branch of cercus with tip reaching base of upper branch in lateral view.

Remarks. The Homonhon Island population differs by being smaller and in having the corners of the shelf of the posterior pronotal lobe shorter. Although Homonhon and Camiguin are in different faunal subregions of the Philippines (Homonhon is in the eastern Visayas subregion and Camiguin is in the Mindanao subregion, Fig. 65 ), both populations are considered to belong to one species here, as the differences are too small to consider them as separate species.

Figures

FIGURE 65. Distribution of S. braulitae (black circle), S. carmelae (black square) and S. feliculoi (black triangle).

FIGURES 1 – 5. Lateral views of male posterior pronotal lobe: (1) S. braulitae holotype; (2) S. bukid paratype; (3) S. dentifer Minadano; (4) S. hamis holotype; (5) S. janvantoli holotype.

FIGURES 8 – 15. Male posterior pronotal lobe, dorsal views: (8) S. braulitae Camiguin; (9) S. braulitae Homonhan; (10) S. bulba holotype; (11) S. circularis Tawi-Tawi; (12) S. dentifer Mindanao, Davao Oriental; (13) S. feliculoi paratype; (14) S. furcata; (15) S. zamboanga holotype.

FIGURES 27 – 32. Lateral views of male synthorax: (27) S. braulitae holotype; (28) S. bukid holotype; (29) S. bulba holotype; (30) S. cahilogi holotype; (31) S. carmelae holotype; (32) S. circularis Tawi-Tawi Island.

FIGURES 41 – 46. Lateral view of male anal appendages: (41) S. braulitae holotype; (42) S. bukid holotype; (43) S. bulba holotype; (44) S. cahilogi holotype; (45) S. carmelae holotype; (46) S. circularis Tawi-Tawi.

FIGURES 53 – 58. Dorsal view of male anal appendages: (53) S. braulitae holotype; (54) S. bukid holotype; (55) S. bulba holotype; (56) S. cahilogi holotype; (57) S. carmelae holotype; (58) S. circularis Sibutu.

FIGURES 6 – 7. (6) S. cahilogi holotype posterior pronotal lobe in dorsal-lateral view. (7) S. carmelae holotype posterior pronotal lobe and part of synthorax in dorsal view, tubercles on mesinfraepisternum visible.