Genus Microsternus Lewis (1887) from China, with description of a new genus Neosternus from Asia (Coleoptera, Erotylidae, Dacnini)
Author
Dai, Cong-Chao
Author
Zhao, Mei-Jun
text
ZooKeys
2013
340
79
106
http://dx.doi.org/10.3897/zookeys.340.6044
journal article
http://dx.doi.org/10.3897/zookeys.340.6044
1313-2970-340-79
Genus
Microsternus Lewis, 1887
Figs 1-2, 3-6, 7-8, 9-12, 13-14, 15-21, 22-23, 24-29, 30-33, 40-42, 45-47, 50-52, 59-64, 73-74, 77-78
Type species.
Megalodacne ulkei
Crotch, 1873
Description
.
Body (Figs 1-2, 7-8, 13-14, 22-23, 73-74, 77-78) small, elongate, with legs short and robust, the tarsi cylindrical, 5-jointed, the four basal joints short, nearly equal in size and not at all dilated, the last joint long. Antennae not very long, the latter with a broad 3-jointed club. Eyes coarsely facetted. Head with the pit posterior to the postmandibular lobes (Figs 40-42). Maxillary and labial terminal palpomeres acuminate, sensory area restricted to apex. Pronotum (Figs 45-47) arched, widest at base; narrowed from base to apex, with formed thinned lines in lateral view (Figs 50-52); disk punctured, except the impunctate medio-basal area, which is limited by an arched transverse row of coarse punctures. Prosternum with median area including its process elevated in an elongate triangular plane, which is distinctly bordered by a ridge on both sides and shortly rounded-subtruncate in front. Mesosternum almost concealed by prosternal process. Metasternum with a pair of mesocoxal lines
strongly
divergent posteriorly. Abdomen without metacoxal lines on basal visible sternite. Elytra convex.
Figures 1-2. Habitus of
Microsternus ulkei
in dorsal and ventral view. Scale = 1 mm.
Figures 3-6. Male genitalia of
Microsternus ulkei
in lateral view 3 Dorsal lobe of
Microsternus ulkei
in dorsal view 4-5 Female genitalia of
Microsternus ulkei
in dorsal view 6. Scale = 1mm (3, 6), Scale = 0.2mm (4, 5).
Figures 7-8. Habitus of
Microsternus pengzhongi
in dorsal and ventral view. Scale = 2 mm.
Figures 9-12. Male genitalia of
Microsternus pengzhongi
in lateral view 9-10 Dorsal lobe of
Microsternus pengzhongi
in dorsal view 11-12. Scale=1mm (9, 10), Scale=0.5mm (11, 12).
Figures 13-14. Habitus of
Microsternus perforatus
in dorsal and ventral view. Scale = 2 mm.
Figures 15-21. Male genitalia of
Microsternus perforatus
in lateral view 15 Internal sac of
Microsternus perforatus
in lateral view 16-17 Dorsal lobe of
Microsternus perforatus
in dorsal view 18-19 Female genitalia of
Microsternus perforatus
in dorsal view 20 Female spermatheca of
Microsternus perforatus
21. Scale=1mm (15, 20), Scale=0.3mm (16, 17), Scale=0.2mm (18, 19), Scale=0.1mm (21).
Figures 22-23. Habitus of
Microsternus tricolor
in dorsal and ventral view. Scale = 1 mm.
Figures 24-29. Male genitalia of
Microsternus tricolor
in lateral view 24-25 Dorsal lobe of
Microsternus tricolor
in dorsal view 26-27 Female genitalia of
Microsternus tricolor
in dorsal view 28 Female spermatheca of
Microsternus tricolor
29. Scale=1mm (28), Scale=0.3mm (24, 25), Scale=0.2mm (26, 27), Scale=0.1mm (29).
Figures 30-33. Elytra of
Microsternus tricolor
in dorsal view.
Distribution.
Microsternus
is widespread in Asia, with one species in Australia and one species in America.
Diagnosis.
Defining characters for
Microsternus
are body elongate, head with the pit posterior to the postmandibular lobes, pronotum without a deep sulcus along each side and narrowed margin in lateral view, mesosternum almost concealed by prosternal process, male genitalia with flagellum (Figs 59-64) bearing a straight mass on apical quarter.
Key to Chinese species of genus
Microsternus
| Figs 22-23 |
Microsternus tricolor
|
|
Figs
7-8
|
Microsternus pengzhongi
|
| Figs 13-14 |
Microsternus perforatus
|