Lestinogomphus nefrens Dijkstra & Mézière, 2015

Dijkstra, Klaas-Douwe B., Kipping, Jens & Mézière, Nicolas, 2015, Sixty new dragonfly and damselfly species from Africa (Odonata), Odonatologica 44 (4), pp. 447-678 : 557-559

Lestinogomphus nefrens Dijkstra & Mézière sp. nov. – Small-toothed Fairytail

(Type Photo 28, Photo 42, Fig. 16)

Taxonomy

While most Lestinogomphus species, including the genus’s type and three new species described here, possess a pair of large teeth near the base of the epiproct, L. congoensis and L. matilei Legrand & Lachaise, 2001 have a smaller set nearer the tip. A taxon associated with the holotype of L. africanus , which lacks appendages, by Fraser (1928) and Pinhey (1961b) also belongs here, but its identity and that of L. africanus remain to be clarified (R. Cammaerts pers. comm.; see Dijkstra & Clausnitzer 2014). For the time being, we name another taxon that is sympatric with L. congoensis in Gabon, but has distinct genetics, male appendages and female occiput (see L. calcaratus sp. nov.) ( Tree 5). Note that the Upper Guinean L. matilei is distinctive by the (1) rather rounded and weakly notched posterior hamule; (2)short S10, its dorsal length being only 1.5–1.7x its apical height; (3)rath- er thick-tipped cerci ( Fig. 16); and (4) epiproct that is not deeply bifid as in other species, but ends in a single blunt tip (best seen in ventral view).

Material studied

Holotype ♂. RMNH.INS.508854 , Gabon, Ngounie Province, Parc National des Monts Birougou , sandy forest stream (1.5 m wide, <20 cm deep), sources and swamp ( Photo 42), 747 m a.s.l. (1.9655°S 12.2188°E), 10-ix-2013, leg. N. Mézière, RMNH .

Further material. GABON (Haut-Ogooué Province): 1♂ ( RMNH.INS.508839 ), as holotype, 05-ix-2013, N. Mézière, RMNH. 1♀ ( RMNH.INS.554495 ), Boumango road, Mopia , sandy and muddy forest stream (1m wide), 433 m a.s.l. (1.8336°S 13.6013°E), 11-xi-2012, leg. N. Mézière, RMNH. 1♀ ( RMNH.INS.554529 ), Moanda-Bakoumba road, forest road on right 25 km from Moanda, Botoso , sandy forest stream, 530 m a.s.l. (1.6939°S 13.0739°E), 24-xi-2012, leg. N. Mézière, RMNH .

Genetics

Four unique haplotypes (n =4) nearest to two specimens tentatively identified as L. angustus from central Congo-Kinshasa, although certain L. angustus was not sequenced ( Tree 5).

Male morphological diagnosis

Very small dragonfly (Hw 20.5 mm; n =1) that recalls the sympatric L. congoensis by (a) being quite dark, with a broad dark band on the fronto-clypeal suture and a thick black rim to the labrum, distinct and straight humeral, interpleural and metapleural black stripes, and the tibiae black without pale streaks; and (b) the pair of small teeth close to the tip of the epiproct dorsum ( Fig. 16). However, (1) the pale area on the collar extends posteriorly of the middorsal tooth, at least in females, as the holotype is too teneral to see this, (2) the ventral section of the interpleural black stripe connects to the humeral marking, rather as shown for L. calcaratus in Fig. 17, while in L. congoensis it extends across the mesepimeron to connect with its dorsal section; (3) the relatively short S10, its dorsal length being 1.8–1.9× its apical height, rather than 2.1–2.2×; and (4) the epiproct is flat rather than raised at its base with longer and more slender branches, the paired teeth are larger and placed basal rather than apical to the deepest point of the notch separating the branches ( Fig. 16).

Etymology

Latin “that cannot bite” refers to the weak teeth on the epiproct (masculine adjective). Range and ecology

Known only from small sandy rainforest streams between 400 and 750 m a.s.l. in southern Gabon. Abundant emergence was observed in the dry season at noon around pools formed behind fallen trees in the stream. The sky can be completely overcast in this season and forest habitats very cool, which may explain the emergence at midday.