Compsoneuria (Siamoneuria) kovaci Braasch, 2005

Braasch, Dietrich & Boonsoong, Boonsatien, 2010, A contribution to the Heptageniidae (Insecta, Ephemeroptera) of Thailand and Malaysia, Zootaxa 2610, pp. 1-26 : 13

Compsoneuria (Siamoneuria) kovaci Braasch, 2005

Some revisional notes on this species are advisable relating to an unnecessary synonymization by Webb and McCafferty (2008). According to the well defined outlines of the genus Compsoneuria by the authors, larval diagnosis of Compsoneuria (Siamoneuria) is in contradiction to that of Compsoneuria , namely in lacking the combination of “long, sharply pointed supracoxal spurs (as in Fig. 79), black spotting on the head capsule and femora, and narrow, apically pointed glossae (Fig. 68)”. Compsoneuria (Siamoneuria) is characterized in male adults by having a hammer-like ecdyonuroid penis head with dorsally well developed lateral sclerites and by absence of ventral spines. Moreover, the larvae are without any features to join them with true Ecdyonurini, for example setate caudal filaments or fimbriate maxillae.

Considering also some larval characters discussed by Braasch (2005), we conclude that Siamoneuria cannot belong in Compsoneuria but probably deserves its own status, a morphospecies possibly independent of other known genera. Further studies on eggs and other larval details are needed for a better assessment of its rightful placement within Heptageniidae (see in Braasch, 2006c, p. 49–50, Figs. 1–21). For now, we see it as a species INCERTAE SEDIS.

Larval characters of Compsoneuria kovaci incertae sedis are: a) unthickened margin of forehead, also in Electrogena Zurwerra & Tomka, 1985 and Thamnodontus Kluge, 2004 ( Webb & McCafferty 2008) ; b) long slender antennae; close standing of labial glossae rounded; c) special gill set: gills III + IV notched and gills V + VI angled; gill VII narrow lanceolate; d) caudal filaments 1.3x longer and 1.2x broader than terminal filament; e) tibiae each with 1 row of long, fine setae; f) rounded supracoxal sclerites (also in Electrogena and Thamnodontus ); g) larvae without median abdominal ridge which is in Notacanthurus Tshernova, 1974 ( Kluge 2004) and in Darthus vadorus Webb &.McCafferty, 2007 .

Adults can be excluded from Thamnodontus and Notacanthurus by lacking anteriorly expanded head capsules and from Electrogena by absence of “teardrop shaped penes with partially fused apical and lateral sclerites” ( Webb & McCafferty 2008).