Yunnanosticta, Dow & Zhang, 2018

Dow, Rory A. & Zhang, Hao-Miao, 2018, Yunnanosticta gen. nov., from Yunnan, a new genus from the Sinostictinae, with the description of two new species (Odonata: Zygoptera: Platystictidae), Zootaxa 4375 (4), pp. 567-577 : 568

Yunnanosticta genus nov.

Type species Yunnanosticta wilsoni sp. nov.

Diagnosis. Small, very slender damselflies. Synthorax in males largely dark brown and black, lacking well defined pale markings dorsally and laterally. CuP meeting wing margin at around midpoint of Fw, well after midpoint in Hw. Wing slightly falcate at tips. Anal appendages with cerci stout, simple in dorsal view, bearing a single sub apical ventral interior spine, paraprocts very broad at base, in lateral view subtriangular to near apex, in ventral view bifurcated at apex.

Remarks. Yunnanosticta is most easily distinguished from Sinosticta by its much smaller size and less robust build, by the synthorax almost entirely lacking pale markings and the vein CuP meeting the wing margin at around the midpoint of the wing in the Fw. In Yunnanosticta the available specimens (all male) have the abdomen plus anal appendages in the range ca 24–29mm, Hw 16.5–19.5mm, in contrast male Sinosticta typically have abdomen plus anal appendages in the range 37–48mm, Hw 27–34mm (based on the measurements given in Wilson 1997, Wilson & Reels, 2001, Wilson & Xu 2007 and Yu & Bu 2009). Yunnanosticta also differs in having fewer (typically none) supplementary post cubital veins. Yunnanosticta species have slightly falcate (hooked backwards) wings (the typical shape in the old world Platystictidae ), however in Sinosticta the wings are not at all falcate (for instance see Figure 1 in Wilson (1997) and Figure 13 in Wilson & Xu (2007)), this character does not appear to have been remarked upon before and should be added to the diagnosis of Sinosticta . The cerci of Yunnanosticta are rather similar to those of Sinosticta except that the paraprocts of Yunnanosticta are slightly more complex structures than those of Sinosticta , with shallowly bifurcated apices. However the discovery of additional species in either genus might blur the distinctions seen in the anal appendages at present. The wing venation, darker colouration, smaller size, and lighter build of Yunnanosticta are the main distinguishing features.

Figures

FIGURES 1–2. Heads of species of Yunnanosticta gen. nov. in dorsal-frontal view: (1) Yunnanosticta wilsoni sp. nov. holotype; (2) Yunnanosticta cyaneocollaris sp. nov. holotype.

FIGURES 10–13. Genital ligula of species of Yunnanosticta gen. nov.; all scale bars 0.2mm. Yunnanosticta wilsoni sp. nov. holotype: (10) lateral view; (12) ventral view. Yunnanosticta cyaneocollaris sp. nov. holotype: (11) lateral view; (13) ventral view.