Porpax mezierei Dijkstra & Kipping, sp. nov.

Porpax mezierei Dijkstra & Kipping sp. nov. – Blue-spotted Pricklyleg (Type Photo 54, Photos 52, 62, 69–70, Fig. 31) Taxonomy

Dijkstra (2006) revised the genus Porpax Karsch, 1896, separating five species principally on the basis of male markings and hind femur ornamentation. Porpax garambensis Pinhey, 1966 was the only species to differ also in the structure of male and female genitalia. The current taxon is morphologically and genetically close to that species but overlaps geographically, differs genetically, and has unique abdominal markings: while other Porpax species are marked with greenish blue, it and the closely related Cyanothemis simpsoni Ris, 1915 seem exceptional among nearly 1 500 libelluloid species for attaining deep blue coloration without pruinosity.

Material studied

Holotype ♂ . RMNH.INS.508827, Gabon, Haut-Ogooué Province, Bongoville-Léconi road after Ekala, old village of Boubou, ponds and humid forest near stream (Photo 70), 393 m a.s.l. (1.6068 ° S13.9137 ° E), 19 -v- 2013, leg. N. Mézière, J. Renoult &J. Lekogo, RMNH.

Further material. GABON (Haut-Ogooué Province): 1 ♂ (RMNH.INS.508823), as holotype, RMNH. 3 ♂, same locality, 28 -xii- 2010, leg. N. Mézière, RMNH. 3 ♂, Bongoville-Léconi road, Boubou River, Ekala, swamp close to the river, 421 m a.s.l. (1.6116 ° S13.9116 ° E), 30 -xii- 2010, leg. N. Mézière, RMNH. 1 ♂ (RMNH.INS.508160), same locality, 27 -i- 2012, leg. N.

Mézière, RMNH. 4 ♂1 ♀ (RMNH.INS.506221), same locality, 20 -xi- 2011, leg. N. Mézière, RMNH. 2 ♂, same locality, 27 -i- 2012, leg. N. Mézière, A. Günther, J. Kipping &H. Krahnstöver, RMNH. 1 ♂ (RMNH.INS.508803), Bongoville-Léconi road, Boubou River, Ekala, sandy forest stream (1–2 m wide, 5–10 cm deep), muddy edges, 427 m a.s.l. (1.6133 ° S13.9124 ° E), 05- iv- 2013, leg. N. Mézière, RMNH. 1 ♂, Bakoumba road, village 3 km before Kounda, Mikouangna (Mouyeugue), large standing water in forest clearing and cassava fields, 520 m a.s.l. (1.6001 ° S13.1584 ° E), 05-ii- 2009, leg. N. Mézière, RMNH. 1 ♂, same locality, 05-iv- 2009, leg. N. Mézière, RMNH.

Genetics Three unique haplotypes (n= 5) distinct from but close to five of P. garambensis (n= 6). Male morphological diagnosis

Structurally like its sympatric sister-species P. garambensis by (a) the dorsally converging pale postdorsal stripes; (b) the densely hairy anterior side of the hind femur and trochanter; and (c) the pointed rather than rounded lobe of the hamule. However, many details are closer to the norm in this genus, such as (1) the larger size, Hw 23.5–25.5 mm (n = 8) rather than 21.5 – 23.0 mm; (2) the large central pale spot on the spiracular dorsum; (3)the black area between the pale postdorsal stripes that is at least as wide as the stripes themselves; (4) the venter of the thorax with the largely pale poststernum and metepimera enclosed by black; (5) normally 2 rather than 1 Cux in Hw, although both species vary between 1 and 3; (6) 11 ½– 12 ½ rath- er than 8 ½– 10 ½ Ax in Fw; and (7) the absence of abdominal pruinosity. Unique in the genus by (8) the pale band on the frons being severed by black medially, as well as at the level of each antenna; (9) the black vertex with at most a weak dorsal spot, rather than a large and contrasting pale patch; (10)S 4–7 with lateral blue spots that extend onto the ventral part of the tergites, but without a ring-like pale marking on S 6; and (11) the blue dorsa of the cerci and epiproct.

Etymology

Named in honour of our co-author Nicolas Mézière who, living in southeastern Gabon, has made many discoveries in this odonatologically unexplored part of Africa within a short time (masculine singular genitive noun).

Range and ecology

Recorded between 350 and 550 m a.s.l. in south-eastern Gabon. Males are found on sunny vegetation by swamps and pools that have much detritus, probably never dry out completely and lie on the forest edge. Not found with P. garambensis as that species prefers similar but deeply shaded habitat with only small sun spots.