Cephaloconnus Franz

Jałoszyński, Paweł, 2017, Taxonomy of ' Euconnus complex'. Part XIII. Status of Afrotropical subgenera of Euconnus: Cephaloconnus, Cerviconnus, Ursoconnus and Nodoconnus (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4294 (5), pp. 531-544 : 533-534

1. Morphological structures and taxonomic status of Cephaloconnus Franz

The general body shape of Euconnus (Cephaloconnus) hypertrophicus ( Fig. 1 ) resembles that of many species of Euconnus (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 posterior margin. The pronotum, however, is not broadest at base, as in the type species of Napochus , but between middle and posterior third. However, the shape of pronotum is variable within Napochus ; species assigned to this subgenus and with the pronota broadest between base and middle are known (e.g., Jałoszyński 2015a, 2017c).

Other characters shared by Cephaloconnus and Napochus are: a short head with the vertex not bulging posterodorsally ( Figs 9 ¯10); the frontoclypeal groove faint or absent ( Fig. 10 ); the hypomeral ridges ( Fig. 11 ; 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. hypertrophicus ); an even number of antebasal pronotal pits ( Fig. 9 ; abp) (one or two pairs of small pits, variable within Napochus ), typically accompanied by short and indistinct sublateral carinae ( Fig. 9 ; slc) (variable within Napochus , but present in its type species and in E. hypertrophicus ); the basisternal part of prosternum ( Fig. 11 ; bst) strikingly short, much shorter than the coxal part; a relatively narrow metaventral intercoxal process ( Fig. 12 ; mtvp) (its width and shape is variable within Napochus ); and the general shape of the aedeagus ( Figs 27 ¯28), except for a distinctly emarginate apex of the median lobe in E. hypertrophicus , whereas the aedeagal apex in most species of Napochus is not emarginate (but the shape of the aedeagus, and especially its apical portion, shows a high degree of variability within Napochus , e.g., see figs 35̄ 54 in Jałoszyński (2015a)).

A striking character of Cephaloconnus , seen in E. hypertrophicus ( Figs 1 , 9 ̄10, 13̄14), is the modified head. The vertex is more convex than in most species of Napochus , the frons is bulging anterodorsally, and these regions are separated by a transverse groove and a rounded ridge ( Fig. 10 ). This modification is restricted to males and small pits at each side of the transverse groove suggest a presence of large cephalic glands (the pits are here interpreted as glandular openings; Fig. 14 ; gop).

Conclusions. The only major morphological difference between the type species of Cephaloconnus and Napochus is the presumably glandular modification of the head in males of the former; females of Cephaloconnus do not differ from those of Napochus , except for having slightly larger heads in relation to the pronotum. Neonapochus Machulka, 1929 , defined solely on the basis of one apomorphy, the modified antennal club in males, was previously placed as a junior synonym of Napochus ( Jałoszyński 2016b) ; the same solution seems reasonable in the case of Cephaloconnus , which also shows an apomorphy restricted to one sex, and additionally a variable one, as Franz (1962) placed in Cephaloconnus species with the head bearing an impression, tooth or a tubercle. Such characters can be used to define species groups within Napochus , but not subgenera. Consequently, Cephaloconnus is placed as a junior synonym of Napochus .

Figures

FIGURES 1 – 8. Dorsal habitus (1 – 4) and set of labels of lectotypes (5, 7 – 8) and a holotype (6) of Euconnus (Cephaloconnus) hypertrophicus Franz (1, 5), Euconnus (Cerviconnus) bundukii Franz (2, 6), Euconnus (Ursoconnus) basilewskyi Franz (3, 7), and Euconnus (Nodoconnus) gomyanus Franz (4, 8).

FIGURES 9 – 12. Morphological structures of Euconnus (Cephaloconnus) hypertrophicus Franz. Head, prothorax and elytral base in dorsal view (9); head in anterior view (10); head and prothorax in ventral view (11); pterothorax in ventral view (12). Abbreviations: abp, antebasal pronotal pit; bst, basisternal part of prosternum; ce, compound eye; fr, frons; gp, gular plate; hr, hypostomal ridge; hyr, hypomeral ridge; lbr, labrum; mn, mentum; msvp, mesoventral intercoxal process; mtvp, metaventral intercoxal process; nss, notosternal suture; pcr, procoxal rest; ptp, posterior tentorial pit; slc, sublateral carina; smn, submentum; vt, vertex.

FIGURES 27 – 34. Aedeagus in ventral (27, 29, 31, 33) and lateral (28, 30, 32, 34) view. Euconnus (Cephaloconnus) hypertrophicus Franz (27 – 28); Euconnus (Cerviconnus) bundukii Franz (29 – 30); Euconnus (Ursoconnus) basilewskyi Franz (31 – 32); Euconnus (Nodoconnus) gomyanus Franz (33 – 34).

FIGURES 13 – 14. Morphological structures of Euconnus (Cephaloconnus) hypertrophicus Franz. Head, prothorax and anterior portion of pterothorax in lateral (13) and slightly dorsolateral (14) views. Abbreviations: bef, basal elytral fovea; fr, frons; gop, glandular opening; gp, gular plate; hyr, hypomeral ridge; msvp, mesoventral intercoxal process; occ, occipital constriction; pre, prepectus; tm, temple; vt, vertex.