An update of Micromyinae (Diptera: Cecidomyiidae) taxonomy, with descriptions of a new genus and 13 new species from Northern Europe
Author
Jaschhof, Mathias
Author
Jaschhof, Catrin
text
Zootaxa
2020
2020-03-12
4750
3
349
369
journal article
10.11646/zootaxa.4750.3.3
7f19f81d-eed1-4d91-a8bd-081b805056ff
1175-5326
3707458
CA4A32B1-04E7-40C6-8EE5-0FA9D331BE21
Ladopyris
gen. nov.
Type
species,
Ladopyris baltica
sp. nov.
, described below. Monotypic.
Diagnosis.
This new genus, which belongs to the tribe
Micromyini (
Jaschhof & Jaschhof 2009: 193
)
, is described here for a single species whose males bear a close resemblance to
Polyardis
Pritchard. Distinctions
concern the genitalic structures, which in
Polyardis
are small, uniform, and of such simplified structure that they might reflect the hypothetical ground pattern of
Micromyinae
(
Jaschhof & Jaschhof 2009
: fig. 18A–B). The genitalia of
Ladopyris
, which are larger and more complex, show the following peculiarities (
Fig. 12
): the sclerotized apex of the tegmen is shaped like a stand-up collar (↓
1
); the parameral apodemes are strongly enlarged (↓
2
); the hypoproct is vestigial; the cerci are prominent (↓
3
); and both the gonostylar body and tooth are flattened (↓
4
). These characters are rated here as significant enough to justify the introduction of a discrete genus (see Discussion). Females and preimaginal stages of
Ladopyris
are unknown.
Etymology.
Ladopyris
is an anagram of
Polyardis
. The gender of the name is female.
Discussion.
Within
Micromyini
,
Ladopyris
is one of three genera in which the bulk of translucent sensilla on the male antenna are slender, single-pointed hairs (
Fig. 11
); the other such genera are
Polyardis
and
Pseudoperomyia
Jaschhof & Hippa. A
singularity of
Pseudoperomyia
is the presence of bottle-shaped sensilla, which occur in small numbers among hair-shaped translucent sensilla (
Jaschhof & Jaschhof 2009
: fig. 11 for a schematic overview of sensilla
types
found in
Micromyinae
). Male morphology provides no clues for the assumption of closer relationship between
Pseudoperomyia
and
Ladopyris
. All the more obvious are the similarities shared by
Ladopyris
and
Polyardis
, such as the sparseness of postocular bristles, the 3-segmented palpus, the sickle-shaped claws, and the claw-long empodia. As mentioned above, the only significant differences concern genitalic structures.
New genera introduced for single species with aberrant genitalic morphology are not unproblematic, more so in the tribe
Micromyini
whose generic classification is in need of fundamental revision (see below the introductory remarks on
Xylopriona
). That said, the pros and cons of taxonomic decisions need to be weighed as cases arrive. We have refrained from classifying
L. baltica
with
Polyardis
– in our view the only alternative possible – because this would require amending the generic definition in an inappropriate manner. It must be remembered that
Polyardis
is an unusually homogenous group of species, of which none shows the slightest sign of aberrant morphology. At the same time, the genitalic structure of
L. baltica
is unusual even with respect to
Micromyini
other than
Polyardis
, in which subtriangular, scutellate tegmina devoid of any substructures prevail. The only exception here is
Pseudoperomyia
, to present knowledge an exclusively Eastern Palearctic / Oriental genus, in which tegmina (as well as other genitalic structures) show a wide range of modifications unknown from other
Micromyini (
Jaschhof & Hippa 1999
)
. The most likely explanation why
L. baltica
at present appears to be such an outlier among
Micromyini
is that its closest relatives remain undiscovered. In other words, we think it likely that further
Ladopyris
will be found in those parts of the Palearctic region where
Micromyinae
are yet unresearched.