A review of fossil taxa of Microphorinae (Diptera, Dolichopodidae sensu lato), with redescription of the Eocene genus Meghyperiella Meunier
Author
Shamshev, Igor V.
Zoological Institute, Russian Academy of Sciences, Universitetskaya nab. 1, St. Petersburg 199034, Russia.
Author
Perkovsky, Evgeny E.
Schmalhausen Institute of Zoology NAS of Ukraine, vul. B. Khmelnytskogo, 15, Kiev, 01030 Ukraine. & Borissiak Paleontological Institute, Russian Academy of Sciences, Moscow, 117997, Russia
text
Zootaxa
2022
2022-06-08
5150
3
411
427
journal article
72886
10.11646/zootaxa.5150.3.6
c8c16c97-1eae-42d2-9ab3-750dc14ea775
1175-5326
6623125
D59052B5-85CD-466F-B4EB-812226DC913E
Microphor
Macquart
Microphor
Macquart, 1827: 139
.
Type
species:
Microphor velutinus
Macquart, 1827
(=
Microphor holosericeus
(Meigen, 1804))
, by subsequent designation (
Rondani 1856
).
Microphorus
Macquart, 1834: 345
. Unjustified emendation.
Microphora
Zetterstedt, 1842: 253
. Unjustified emendation or error, not
Microphora
Kröber, 1912: 245
(=
Therevidae
).
Included fossil species.
Microphor rusticus
(
Meunier, 1908
)
: 105 (
Phyllodromia
, male and female) (Baltic region, Upper Eocene).
Remarks.
Microphor
remains a broadly defined group with not quite clear phylogenetic background. The very recently published revision of the North American species provides the first provisional evidence of monophyly of this genus, especially with respect to
Schistostoma
(
Brooks & Cumming 2022
)
.
Currently,
Microphor
comprises 16 known extant and one extinct species. The recent species are distributed mostly in the Holarctic, one species was described from mountains of South
China
and one unnamed species is known from South
Chile
(
Chvála 1991
;
Saigusa & Yang 2003
;
Brooks & Cumming 2022
).
The single fossil species of
Microphor
was described by
Meunier (1908)
from Baltic amber recognized in the genus
Phyllodromia
(Empididae)
.
Hennig (1971)
examined the type series of
M
.
rusticus
and indicated the correct systematic position of this species (also designated the
lectotype
). However, he did not provide a full redescription of
M
.
rusticus
but included figures of the female habitus as well as the male head, wing and postabdomen (
Hennig 1971
: figs 26–29). It should be noted that
M
.
rusticus
may actually be a species of
Schistostoma
because
Hennig (1971)
did not separate
Microphor
and
Schistostoma
. As recently re-defined,
Schistostoma
differs from
Microphor
primarily by medial hypandrial prolongation of the male genitalia (
Brooks
et al
. 2019
;
Brooks & Cumming 2022
). However, the structure of the hypandrium is invisible on Hennig’s figure 28 (illustrated from the left side and obscured by pregenital segments). In addition, the female of
M
.
rusticus
apparently has at least six visible abdominal segments (
Hennig 1971
: fig. 26) that matches with another possible apomorphic feature of
Schistostoma
(
versus
5 exposed segments in
Microphor
) (
Brooks & Cumming 2022
).
Microphor rusticus
has two pairs of scutellar setae (
Hennig 1971
: fig. 26) that is usually present in
Schistostoma
(
versus
3–4 pairs in
Microphor
), however, this character is somewhat variable (
Shamshev & Sinclair 2006
;
Brooks & Cumming 2022
). It seems that
Hennig (1971: 5
, fig. 4) did not illustrate correctly the stylus segmentation in
M
.
rusticus
. Actually, the basal article of the stylus is much shorter and hardly distinguishable, contrary to
Ulrich (1991: 212
;
2004: 235
) who considered the basal article to be absent in this species.
Microphor rusticus
is probably present in
Rovno
amber. We have examined two very well-preserved inclusions that are apparently a mated male and female (Shamshev & Perkovsky, unpub. data). In addition, an undescribed species with an incomplete vein M
2
found in
Rovno
amber, which has been mentioned under
Meghyperiella
, probably is another representative of
Microphor
. Although
Microphor
is known from the Eocene, it must exist at least in the mid-Cretaceous because both its closest allies (i.e.,
Schistostoma
and
Microphorites
) were recorded from that time.