Acronymolpus jourdani (Jolivet, Verma & Mille, 2013) Jolivet, Verma & Mille, 2013

Gomez-Zurita, Jesus, 2017, Insights on the genus Acronymolpus Samuelson with new synonymies and exclusion of Stethotes Baly from the fauna of New Caledonia (Coleoptera, Chrysomelidae, Eumolpinae), ZooKeys 720, pp. 65-75 : 68-69

Acronymolpus jourdani (Jolivet, Verma & Mille, 2013) comb. n.

= Acronymolpus gressitti Samuelson, 2015, syn. n.

= Acronymolpus joliveti Samuelson, 2015, syn. n.

Material examined.

HNHM: (1) one male and one female, New-Caledonie, Mont Panié, 7.ii.1977, leg. Dr. J. Balogh, Acronymolpus jourdani (Jolivet, Verma et Mille) J. Gómez-Zurita det. 2017. MNHW: (1) one female, New Caledonia (N), Mandjélia (summit) 20°23.9'S, 164°31.9'E, 750-780 m, beating, montane rainforest, leg. M. Wanat & R. Dobosz, Acronymolpus jourdani (Jolivet, Verma et Mille) J. Gómez-Zurita det. 2017.

Remarks.

A few years after the description of S. bertiae , Jolivet et al. (2013) described another species of Stethotes , S. jourdani , very similar to the former but with subtler punctation and from localities further north in the island, in the Massif du Panié, including La Guen, Dawenia, and Wewec ( Jolivet et al. 2013). As before, the species does not have any of the characters of the genus Stethotes , but these of Acronymolpus instead. Interestingly, it fits the description of the second blackish species of Acronymolpus described by A. Samuelson a couple of years later, A. gressitti , also collected from Mt. Panié. It is worth noting that both descriptions depart in a significant character: the size of the holotypes. The type of S. jourdani is reported as 4.0 mm long ( Jolivet et al. 2013), while that of A. gressitti is 2.6 mm ( Samuelson 2015). The measurement given by Jolivet et al. (2013) is far bigger than the largest Acronymolpus studied by Samuelson (2015). However, it is important to note that, judging from the figures in the article, the measurements in Jolivet et al. (2013) may not be reliable. Samuelsonia gomyi Jolivet et al., 2013 measures 2.5 mm and it shows slightly longer than the holotype of S. jourdani , figured alongside and possibly photographed with the same magnification as the former, since both show an identical scale bar of 2.0 mm ( Jolivet et al. 2013, figs 7 and 8). Apart from this detail, the two species, S. jourdani and A. gressitti , match in their characters, as recognized by the author of the latter (G. Allan Samuelson, pers. comm.), including the four basal antennomeres paler, vertex deeply sulcate, smooth hypomera, and pronotal and elytral punctation smaller than in S. bertiae .

Moreover, additional material, even if limited, made it possible to draw an analogy with the previous case whereby A. joliveti could be recognized as the female of A. gressitti . The spermatheca of this species was known due to the description of A. joliveti , and the only information available on the male genitalia was a drawing of the penis in lateral view ( Jolivet et al. 2013: fig. 1). The spermatheca of A. jourdani , figured here from a specimen from Mandjélia, is identical to that figured by Samuelson (2015) from a specimen from Mt. Panié (Fig. 1f). This spermatheca is very similar to that of A. bertiae , but shows some relevant differences, including a straight nodulus longer than cornu, conspicuously dilated at base and constricted medially at both ends of bulging insertion of spermathecal gland. Here, the first complete description of the penis of A. jourdani is provided and is a very useful character to distinguish this species from A. bertiae (Fig. 1b, d). The penis is similar to that of A. bertiae with a less pronounced ventral curvature and more gradually curved apex; and the apical end, as seen in dorsal view, has straight sides converging to an acute apex with a deep, narrow median cleft.

As before, three taxonomic acts are required, the first transferring Stethotes jourdani to Acronymolpus , to propose the new combination Acronymolpus jourdani (Jolivet, Verma & Mille, 2013), comb. n., and the second establishing that A. gressitti and A. joliveti are junior synonyms of this taxon, thus Stethotes jourdani Jolivet, Verma & Mille, 2013 = Acronymolpus gressitti Samuelson, 2015, syn. n. and Acronymolpus joliveti Samuelson, 2015, syn. n.