Comparative morphology and taxonomy of Sciacharis s. str., Chathamaenus Franz and Maorinus Franz (Coleoptera: Staphylinidae: Scydmaeninae)
Author
Jałoszyński, Paweł
text
Zootaxa
2014
3794
2
222
236
journal article
45869
10.11646/zootaxa.3794.2.2
4dab3d72-ed90-4061-959c-1a39618b69ec
1175-5326
230988
E75F9E63-4785-49AB-AD6D-AC4838F39BAD
subgenus
Maorinus
stat. n.
Maorinus
Franz, 1980a
: 291
; replacement name for preoccupied
Maoria
Franz
; elevated to the genus rank by
Kuschel (1990)
.
Maoria
Franz, 1975
: 14
; as subgenus of
Euconnus
, preoccupied,
nec
Laporte, 1868
,
nec
Pilsbry, 1892
,
nec
Warren, 1912
,
nec
Cameron
, 1945
.
Type
species:
Phagonophana alacer
Broun, 1915
(des. orig.).
Revised diagnosis.
A subgenus of
Sciacharis
that differs from
Sciacharis
s. str.
in internal (adcoxal) part of prothoracic hypomeron anteriorly demarcated from prosternum and posteriorly fused with external part of hypomeron; and in mesoventral intercoxal process continuous, not interrupted in middle, distinctly visible in ventral view in intact specimens as moderately narrow carina with finely setose ventral surface clearly separating mesocoxae.
Remarks
.
Maorinus
(as
Maoria
) was described as a subgenus of
Euconnus
characterized by a strongly convex body and usually long and at least in some places dense and erect setation (
Franz 1975
). This diagnosis is certainly highly unclear and matches many species of
Euconnus
-like
Cyrtoscydmini
from all continents.
Franz (1975)
compared
Maorinus
(as
Maoria
) to
Euconnus
subgenus
Tetramelus
Motschulsky, 1870
and listed some characters to distinguish these taxa. In my opinion similarities between
Maorinus
and
Tetramelus
are only superficial and it remains unclear why Franz associated the morphology of both genera. It is also unclear why
Kuschel (1990)
elevated
Maorinus
to the genus rank, and why Franz accepted this decision, in opposition to
Magellanoconnus
, which was also treated by
Kuschel (1990)
as a genus (again, without giving any reasons) but retained by
Franz (1993
,
1997
) as a subgenus of
Sciacharis
.
The morphology of
Maorinus
, although the general appearance (Figs. 4–5) seems distinct from
Sciacharis
, is highly similar to structures of
Sciacharis
s. str.
(as shown in
Figs. 10–11
,
16–17
and
21
) and differs in two easily observable details (indicated in
Figs. 17
and
21
by arrows). The internal (adcoxal) part of each prothoracic hypomeron is anteriorly strongly narrowing and completely demarcated from prosternum (anteriorly indistinctly separated or even fused with prosternum in
Sciacharis
s. str.
) and the posterior parts of hypomeral ridges are obliterated, so that adcoxal and external parts of hypomera are fused posteriorly (demarcated in
Sciacharis
s. str.
). The mesoventral intercoxal process in
Maorinus
is not interrupted in middle and forms a long carina distinctly separating mesocoxae. The carina, in contrast to
Euconnus
, is not expanded ventrally beyond the level of mesocoxae, and the metacoxae are contiguous (broadly separated in
Euconnus
).
Species of
Maorinus
are usually (but not always) larger, more robust, more convex and darker than
Sciacharis
s. str.
Additionally, the vertex in
Maorinus
can be slightly expanded dorsocaudad, but not strongly and subconically, as in some species of
Euconnus
; also the metaventral intercoxal process can be shallowly notched in middle. However, only minor differences in the important structures as the head venter, prosternum and pterothorax were found and they do not justify a separate position of
Maorinus
as a genus. Therefore, this taxon is here reduced to a subgenus of
Sciacharis
.
A preliminary study revealed that at least some Australian,
New Zealand
and New Caledonian species of
Sciacharis
(
Magellanoconnus
)
do not differ in any important characters from
Sciacharis
(
Maorinus
)
, but also some of them have slender, and not expanded maxillary palpomere III. However,
Magellanoconnus
is also distributed in South
America
and
South Africa
and its morphology and taxonomic status requires a separate analysis.