Taxonomic review of the genera Micridium Motschulsky, 1869 and Micridina Johnson, 1969 (Coleoptera: Ptiliidae) with eleven new species including the first records from South America and Madagascar
Author
Darby, Michael
text
Zootaxa
2017
4242
2
233
254
journal article
36307
10.11646/zootaxa.4242.2.2
c4e5d710-edf2-4928-b53d-22c211fcad53
1175-5326
376374
0DD1868D-4EF5-4FB7-AEE9-372644800A79
Micridium rhodeanum
(
Casey, 1924
)
as
Dilinium rhodeanum
(
Figs. 5
,
30
,
60
,
71
, 90a, 90b, 99)
Micridium rhodeanum
(Casey)
;
Johnson (2001)
Habitus
Fig. 5
. Length
0.65 mm
. Colour yellow brown, legs and antennae yellow. Antennomeres 3–11 length
0.22 mm
. Width across eyes
0.19 mm
. Mentum narrowed towards base, lateral margins straight. Pronotum
0.25 mm
wide,
0.19 mm
long, with two distinct elongate depressions reaching from the posterior margin to just past the middle, the distance between them narrowing anteriorly; sides slightly sinuate before hind angles,
Fig. 30
. Elytra
0.40 mm
long,
0.30 mm
wide, widest just in front of middle. Mesoventrum: keel narrow between mesocoxae, collar with two short ridges extending posteriorly between the keel and the mesepiventral ridges which are faint, mesepiventra without obvious reticulation
Fig. 60
. Metaventrum: metepiventral sutures faint, angled inwards and extending half way to posterior margin
Fig. 71
; intercoxal process evenly rounded with comb of +/- 24 narrow setae Fig. 99. Wings of usual ptiliid
type
.
Male: aedeagus Figs. 90a/b.
Remarks.
Five Casey
syntypes
(labelled as ‘paratypes’; designated as
paralectotypes
by Sörensson) (
Fig. 5
) were borrowed for study from the
Smithsonian Institution
,
Washington DC
,
USA
.
One
was remounted as a disarticulated slide in
Euparal
on a piece of acrylic attached to the pin and a male and female remounted on cards for examination in the SEM.
No
genitalia were detected in the female and further dissections were not carried out on the other very fragile specimens for the reasons given above.
I have also seen what appear to be two further examples of this species mounted on a single card, collected by
R.Coleman
in
Fairfield Township
,
Sank Co.
,
Wisconsin
,
USA
,
30 Oct. 1953
, in leaf mould and bearing the determination label '
Micridium
sp.
Dybas
&
Johnson'
(MM).