2. Morphological structures and taxonomic status of Cerviconnus Franz

The general body shape of Euconnus (Cerviconnus) bundukii (Fig. 2) resembles that of many species of Napochus; especially in the antennae with 4-segmented and sharply demarcated club and the pronotum broadest behind middle and strongly narrowing anteriorly, with obtuse-angled but well-marked posterior and anterior corners and the anterior margin much shorter than the posterior margin. The antennal club, however, is not composed of antennomeres broader than long (except XI), as those in the type species of Napochus, but all antennomeres of the club are distinctly elongate. The shape of antennomeres, both those forming the club and proximal ones, is variable within Napochus, but typically the antennomeres IIĪVII are subcylindrical and compactly assembled, and VIIĪX transverse and loosely assembled, each distinctly narrowing both toward base and toward apex. Some of these features can be found in Cerviconnus: the antennomeres IIĪVII are subcylindrical and compactly assembled, and VIIĪX are loosely assembled and each is distinctly narrowing proximally and distally. Therefore, only the length of antennomeres forming the sharply demarcated club is different.

Other characters shared by Cerviconnus and Napochus are similar as those listed for Cephaloconnus and Napochus: a short head with the vertex not bulging dorsally (Figs 15 ̄16), although distinctly projecting posteriorly (Fig. 16); the frontoclypeal groove faint or absent (Fig. 16); the hypomeral ridges (Fig. 17; hr) nearly complete and typically strongly convergent posteriorly; the thick bristles on tempora and sides of prothorax (in some cases reduced in Napochus, but present in its type species and in E. bundukii); an even number of antebasal pronotal pits (Fig. 15; abp) (one or two pairs of small pits, variable within Napochus), typically accompanied by short and faint sublateral carinae (Fig. 15; slc) (variable within Napochus, but present in its type species and in E. bundukii); the basisternal part of prosternum (Fig. 17) strikingly short, much shorter than the coxal part; a relatively narrow metaventral intercoxal process (Fig. 18; mtvp) (its width and shape is variable within Napochus); and the general shape and structures of the aedeagus (Figs 29 ̄30).

Conclusions. The only morphological difference between the type species of Cerviconnus and Napochus is the shape of antennomeres VIIĪX, which are distinctly elongate in the former and transverse in the latter. Species of various tropical areas matching the diagnosis of Napochus and having the antennomeres VIIĪX about as long as broad were seen by the author, and therefore defining a subgenus solely on the basis of the length of three antennomeres would lead to ambiguous diagnoses. Consequently, Cerviconnus is placed as a junior synonym of Napochus .