Prodasineura hoffmanni, Kosterin, Oleg E., 2015

Kosterin, Oleg E., 2015, Prodasineura hoffmanni sp. nov. (Odonata, Platycnemididae, Disparoneurinae) from eastern Cambodia, Zootaxa 4027 (4), pp. 565-577 : 566-573

Prodasineura hoffmanni sp. nov.

( Figs. 1–2 , 3 a,c, 4)

Type material. Holotype: ♂ ( Fig. 2 a–b,d–h), Cambodia, Mondulkiri Province, 4.2 km SE of Dak Dam village, ‘Seducta brook’ [conventional nickname], 12°23'10–18'' N 107°19' 22–30'' E, 877–878 m asl, 14 vi 2014, O. Kosterin leg., deposited in RMNH. Paratypes: 4♂ ( Fig. 2 c,i), 1♀ ( Fig.4 ), data as for the holotype, deposited in BMNH, RMNH, ZMUM and the author’s collection; 1♂ ( Fig. 2 j), Cambodia, Mondulkiri Province, Cambodia, Mondulkiri Province, Dak Dam village environs, a rivulet bank, 12°25' N 107°19' E, ~ 780 m asl, 16. VI. 2014, O. Kosterin, in RMNH.

Additional datum. A photo of ♀ ( Fig. 1 c), the data as for the last paratype.

Etymology. The species is named after Joachim Hoffmann as recognition of his activities to promote International Dragonfly Fund; the specific epithet is a noun of the masculine gender in the genitive case.

Holotype male. Head ( Fig. 2 d): mostly black. Labium blackish but base of mentum and sides of movable hooks yellowish. Genae blue and postclypeus lower parts broadly blue. Vertex with a broad transverse azure blue band with very irregular margins, continuous but nearly interrupted at middle and behind antenna bases. Apex of 1st antennal segment yellowish, that of 2nd brown. Occiput with a straight transverse ridge behind ocelli ( Fig. 2 d). Eyes in life with a brownish black upper half and azure blue lower half ( Fig. 1 a); post mortem brown ( Fig. 2 a,d).

Thorax: Prothorax black with a large azure-blue spot on either side of median lobe occupying also lateral corners of anterior lobe; posterior lobe entirely black ( Fig. 1 a, 2d). Synthorax ( Figs. 1 a–b, 2a,h) black with the following azure-blue pattern ventrally lightening to bluish-white:

– mesepisternum with about 40% as narrow antehumeral stripe, narrowing apically but ending bluntly about 0.014 mm before antealar ridge;

– metepisternum with a broad stripe occupying most of its breadth, embracing spiracle at its lower margin and having a shallow incision at upper 1/3 of its anterior margin;

– metepimeron lower half bluish (but lower margin and posterior corners black); – oval azure-blue spots on sclerites in front of base of each wing and between hindwings; – poststernum whitish at middle, blackish at side.

Post mortem antehumeral stripes turn violet while ventral parts of light markings turn yellowish. Legs black but protrochanters, trochanters and bases of femora ventrally yellowish white and each tibia with a yellow stripe along posterior side ( Fig. 2 a).

Wings hyaline; venation black. Anal bridge present, slightly longer than distance from its distal end to 1st crossvein on forewing, slighly shorter on hindwing. Postnodals 16 (left)–17 (right) on fore wings, 14 (right)–15 (left) on hindwings. Pterostigmata black with faint yellowish rims.

Abdomen ( Figs. 1 a–b, 2a–b,e–i, 3a): Black with the following light pattern:

– S1 with a narrow triangular, with rounded corners, blue spot at posterior margin and a bluish white spot along lower margins ( Fig. 2 a);

– S2 with a narrow blue dorsal streak and a broad bluish white stripe along lower margins ( Fig. 2 a);

– S3–7 with a dorsally interrupted semirings along anterior margin ( Figs. 1 a–b, 2b); – S3–6 with a pair of small yellowish spot at lower margins at about ¾ of segment length ( Fig. 2 b); – S7–8 with yellowish posterolateral corners ( Fig. 2 b);

– S9 with a very small elongate dorsal blue spot at about ¾ of its length ( Fig. 2 f);

– S10 dorsal half azure blue, its borders making pointed projections ventrally ( Figs. 1 a, 2g –j);

Cerci azure blue dorsally, black apically, tips yellowish ( Fig. 2 g–j). Paraprocts outer surface black, inner surface brownish ( Fig. 2 e–g). Cercus with a very robust blunt ventral tooth, normally not well seen behind paraproct; in lateral view, cercus ventroposterior margin between this tooth and apex only slightly concave, almost straight ( Fig. 2 h–j, 3a). In dorsal view, cerci evenly broad in basal half, then processed and very slightly diverging ( Fig. 2 g). Paraproct outer margin in lateral view almost parallel to that of S10, in lower part processed and broadened almost as a short club ( Fig. 2 g–i, 3a) where paraproct ventral margin wraps inwardly ( Fig. 2 e).

Measurements (mm). Abdomen without anal appendages 32; hindwing 21; forewing 21; total length 38.

Variation in male paratypes. Little. Antenodals 14–17 on fore wing, 13–14 on hindwing. In the paratype from Dak Dam, the transversal stripe on the vertex is completely thrice interrupted with black. The wing membrane is slightly enfumed with brownish in all paratypes but to different extent. Ranges of measurements (mm): abdomen without anal appendages 29–32; hindwing 19–21; total length 35–38.

Female. Head ( Fig. 4 i–k): Mentum dull-greyish with indistinct dark pattern consisting of triangular central spot, a pair of lateral spots, and an elongate basal streak. Movable hooks brown at bases, black at tips ( Fig. 4 k). Labrum yellow with a black central spot and brownish black anterior margin. Mandible bases, genae and lower part of postclypeus yellowish blue so that face is of that colour up to the level of anteclypeus upper margin, but ventrolateral corners of postclypeus black ( Fig. 4 j). Rest of head black but vertex with a bluish white transverse stripe as in male but narrowly interrupted in front of central ocellus ( Fig. 4 i). Apical parts of antennal segments brown. Eyes in life with a black upper half, interrupted by a narrow greenish horizontal streak ( Fig. 1 c), and bluish lower half; post mortem brown ( Fig. 4 i–k).

Thorax: Prothorax black with a large bluish spot on either side of median lobe extending to lateral corners of anterior lobe; anterolateral margins of the latter with additional yellowish lightening; lateral corners of posterior lobe bluish ( Fig. 4 c,e). Posterior lobe with a pair of raised bluntly pointed anterior processes in frontal view resembling dog’s ears, in lateral view smoothly curving anteriorly ( Fig. 4 e). Posterior processes broad, rounded, skewed at ca 30–40º to horizontal space, directed behind and converging towards each other, with their axes forming an angle of ca 80º ( Fig. 3 c, 4c). Space between posterior processes narrower than their own width, space between anterior processes broader, so that posterior ones disposed almost between them ( Fig. 3 c, 4c). Space behind posterior processes yellowish. Synthorax black with a bluish white (becoming yellowish near ventrum) pattern as in male but antehumeral stripes narrow, about 20% as narrow as mesepisternum ( Fig. 4 a–b).

Legs bicolored: anterior side of coxae, protrochanters, trochanters, base and ventral side (except for distal 1/3) of all femora and dorsal side of all tibiae yellowish white, the rest of legs black ( Fig. 4 a).

Wings hyaline; venation black, pterostigmata brownish. Postnodals: 16 (left)–17 (right) on forewings; 15 on hindwings.

Abdomen ( Fig. 4 a, f–h): Black with the following pattern:

– S1 patterned as in male but with yellowish ( Fig. 4 a);

– S2–4 with a very faint bluish dorsal streak ( Fig. 1 c);

– S2–4 with broad yellowish stripes along lower segment margins (except for their distal parts), obscured (especially on S4) by diffuse melanisation spreading from the very margins ( Fig. 4 a).

– S8–9 with distinct whitish stripes along ventral margins ( Fig. 4 f–g);

– S3–6 with a pair of elongate white spots at anterior margin ( Fig. 1 b–c);

– S6–9 with greyish lightening at posterior margins;

– S8 with a whitish dorsal streak and S9 with a spoon-shaped whitish dorsal spot ( Fig. 1 c,4h);

– S10 whitish at dorsum and along posterior margins, borders of whitish slanting towards lateroposterior corners ( Fig. 1 c,4f–h);

– cerci whitish above but tips black; paraprocts black ( Fig. 4 f–h);

– ovipositor black but distal ends of sclerites brownish ( Fig. 4 g).

Measurements (mm). Abdomen without anal appendages 32; hindwing 21; forewing 22; total length 37.

Short diagnosis. A Prodasineura with blue markings in males and whitish markings in females; head with a broad irregular, nearly thrice-interrupted blue/bluish stripe; males with antehumeral stripes about twice as narrow as mesepisternum, in females narrower; in males, blue pattern at end of abdomen confined to a tiny oval spot on S9, dorsum of S10 and cerci; in females, whitish pattern of abdomen confined to dorsal spots on S8 and S9 and dorsum of S10 and cerci; male cercus with a ventral tooth at submedian position, paraproct slightly club-like, expanded ventrocaudally in lateral view; in females, posterior prothorax processes converging.

Differential diagnosis. Males of P. hoffmanni differ well from most other blue-patterned Asian species of Prodasineura by the blue colour at the tip of the abdomen almost confined to S10 and appendages (the dorsal side of both entirely), with a tiny oval blue spot on the dorsum of S9. In P. doisuthepensis , the abdominal pattern is similar, but the spot on S9 is much larger, occupying 1/3–1/4 of the segment length. In P. coerulescens , P. fujianensis , P. theebawi , P. y ul an Dow et Ngiam, 2013, and also Elattoneura campioni Fraser, 1922 , the blue colour is present on S8–10; in Prodasineura abbreviata Lieftinck, 1951 , P. integra (Selys, 1882) , P. interruptra , P. hangzhongensis , P. laidlawi and P. quadristigma Lieftinck, 1951 , it broadly occupies S9–10; in P. collaris , P. lansbergei (Selys, 1886) and P. si ta it is confined to the appendages only and is absent at the end of abdomen in P. notostigma .

The shape of appendages provides important characters: the cercus with one broad and blunt ventral tooth disposed submedially, the paraprocts with inflated and wrapped inwardly apices. This shape resembles P. doisuthepensis , in which the cerci are more pointed and look narrower in ventral view as the inflation with the tooth is oriented more inside ( Fig. 3 b), while in P. hoffmanni more downward ( Fig. 2 g–i,3a). Also, in P. hoffmanni the paraprocts are somewhat less attenuated apically ( Fig. 3 a) than in P. doisuthepensis ( Fig. 3 b). The pattern of the end of abdomen is also similar, differing in the S9 blue spot much smaller in P. hoffmanni . In addition, in the Cambodian males of P. doisuthepensis the paraproct apices are yellow, although black, as in P. hoffmanni , at the type locality ( Hoess 2007). However, an almost half as wide antehumeral stripe is the striking difference of P. hoffmanni from P. doisuthepensis (which was found about 14 km NW from the type locality of the former, at Sen Monorom).

These moderately broad and pointed posteriorly antehumeral blue stripes are less broad and at the same time less gradually tapering to their tips than in P. c o l l ar i s and P. notostigma . P. notostigma has the top the head entirely black, while P. collaris has a blue posterior lobe of the prothorax and a blue labrum, genae and mandible bases, which are black in the new species.

Females are not described for many of the above-mentioned species, so truly diagnostic features of the new species in this sex cannot be provided at present. The following characters of the new species female can be mentioned: very uneven, broad but almost thrice-interrupted transverse blue stripe on the vertex; a yellow labrum with a black central spot and black anterior margin; black anteclypeus; S10 with whitish dorsum and distal margin, S8 and S9 with whitish dorsal strokes. The shape of the processes of the prothorax posterior lobe is characteristic: anterior processes are triangular and anteriorly curved, and posterior processes are broadly rounded, directed backward and converging ( Fig 3 c,4c). In P. doisuthepensis (see below and Fig. 3 d, 6g –f), the posterior processes are set more widely apart from each other and do not converge. In P. coerulescens , the posterior processes are set far more widely apart from each other, while the anterior processes are narrow and pointed ( Asahina, 1984).

Remarks. The new species surely belongs to a group of species (certainly not monophyletic) with blue-banded males ( Lieftinck 1951) presently attributed to Prodasineura . Most of them differ from each other by some constant features of the blue pattern on the head, thorax and end of abdomen, in spite of some variation (but some species are still known by single specimens only). This group is represented in continental Asia by the following species: P. doisuthepensis , P. coerulescens , P. collaris , P. interrupta , P. laidlawi and P. n ot os t i g m a. Elattoneura campioni , although having a complete anal bridge which was a reason of its current placing in Elattoneura , is most probably related to this group as well, as Elattoneura and Prodasineura in their current state are rather artificial genera demanding revision ( Dijkstra et al. 2014). The purely island representatives of this group are P. abbreviata , P. lansbergei , P. quadristigma Lieftinck, 1951 , and P. y ul an from Borneo ( Lieftinck 1951; Dow & Ngiam 2013), P. integra from the Philippines ( Hoess 2007). In P. s i t a from Ceylon, the pattern strongly darkens in mature males ( Fraser 1933; Bedjanič et al. 2014). P. theebawi , P. hanzhongensis and P. fujianensis seem to be less closely related to the aforementioned species but related to each other (e.g. all have chrome-yellow colour extensively present on the anal appendages), their light pattern colour varying from blue to yellow.

Habitat. The type locality ( Fig. 5 ) is a small, shallow, shady brook with dark bottom and smooth moderate current, difficult to follow because it is crossed by many (each ca 20 m) fallen trees of different age; there are sparse Cyathea sp. tree ferns among understorey at banks. It is situated at 877–878 m asl in a deep and narrow forested dell in a primary forest patch ca 4.3 x 2.5 km in size occupying a valley in a grassy savannah plateau; some of plots of this patch are being currently logged.

In this habitat, the new species co-occurred with the second species of the same genus, Prodasineura verticalis sensu Asahina, 1983 , nec Selys, 1860 (see Asahina 1983; Hämäläinen & Pinratana 1999), the males of which have an orange pattern. Larger streams and rivers in the same province revealed two other species of Prodasineura , P. autumnalis and P. doisuthepensis .

Distribution. So far P. hoffmanni is known only from two very close localities in Mondulkiri Province of Cambodia (at highest elevations within it), which is just 6.2 km NNE from the border of Vietnam (Lâm Đồng Province). The range of the species is expected to occupy the Central Plateau of the Annamese Mountains in E Cambodia and S Vietnam. Probably the species is also present in Laos (see below).

Figures

FIGURE 1. Prodasineura hoffmanni sp. nov. in nature: a—male; b— tandem, in the type locality (Cambodia, Mondulkiri Province, 4.2 km SE of Dak Dam village), 14. VI. 2014.; c—female at the other locality at Dak Dam village, 16. VI. 2014.

FIGURE 2. Details of male of Prodasineura hoffmanni; a – b, d – h—holotype, c, i—paratype from the type locality; j—paratype from the second locality; a—habitus of head, thorax and S 1 – 3 of abdomen, lateral view; b – S 6 – 10 of abdomen, lateral view; c—synthorax, dorsal view; d—head, dorsal view; e—end of abdomen, posterior view; f— ditto, ventral view; g— ditto, dorsal view; h – j— ditto, lateral view. Not to scale.

FIGURE 3. Comparative sketches of the male anal appendages in lateral view (a – b) and female prothorax in dorsal view (c – d) of Prodasineura hoffmanni (a, c) and P. doisuthepensis (b, d). Colour borders are indicated with dots.

FIGURE 4. Details of female of Prodasineura hoffmanni; a—habitus of head, thorax and S 1 – 3 of abdomen, lateral view; bsynthorax, dorsal view; c—prothorax, dorsal view; d— ditto, frontal view; e— ditto, lateral view; f— S 6 – 10 of abdomen, lateral view; g—end of abdomen, lateral view; h— ditto, dorsal view; i—head, dorsal view; j— ditto, frontal view; k— ditto, ventral view. Not to scale.

FIGURE 5. Habitat of Prodasineura hoffmanni in the type locality: Cambodia, Mondulkiri Province, 4.2 km SE of Dak Dam village, ‘ Seducta brook’ in a forest dell, 877 – 878 m asl, 14. VI. 2014.