A review of Afrotropical Porricondylinae (Diptera: Cecidomyiidae), with descriptions of five new species of Asynaptini from KwaZulu-Natal Province South Africa
Author
Jaschhof, Mathias
0000-0003-3447-1620
Station Linné, Ölands Skogsby 161, SE- 38693 Färjestaden, Sweden. & mjaschhof @ yahoo. de; https: // orcid. org / 0000 - 0003 - 3447 - 1620
mjaschhof@yahoo.de
Author
Jaschhof, Catrin
0000-0002-1030-0934
Station Linné, Ölands Skogsby 161, SE- 38693 Färjestaden, Sweden. & https: // orcid. org / 0000 - 0002 - 1030 - 0934
text
Zootaxa
2023
2023-02-20
5244
3
261
275
http://dx.doi.org/10.11646/zootaxa.5244.3.4
journal article
56315
10.11646/zootaxa.5244.3.4
10c70395-38c4-4847-b4bf-86522cbd3baf
1175-5326
7656363
4212B66F-DE64-4425-A4DE-674A36DDDCC8
Redefinition of
Asycampta
within the
Pseudocamptomyia
group of genera
(A) Context. Although not explicitely stated in the publication,
Mamaev & Zaitzev’s (1997)
decision to associate two new
Asynaptini
from Somalian material with the then monotypic, Nearctic genus
Pseudocamptomyia
(
type
species:
Asynapta phosphila
Felt
), was presumably determined by male terminalia characters. While these authors ascribed one species (
africana
) to
Pseudocamptomyia
s. str.
, the other (
palpata
) was classified in a new subgenus,
Asycampta
, distinguished on three characters: the number of palpal segments, the dentition of the tarsal claws, and the outline of vein
CuA
.
Asycampta
was defined as having a foreshortened, 2-segmented palpus, toothless claws, and distinct vein
CuA
, whereas
Pseudocamptomyia
s. str.
was characterized as having a long, 4-segmented palpus, unidentate claws, and indistinct vein
CuA
. While
Mamaev & Zaitzev (1997)
failed to clarify the meaning of “distinct” and “indistinct” with respect to vein
CuA
, the other two characters were useful for separating the two subgenera. The same system ceases to work, however, when additional species are taken into consideration. In
Asycampta karkloofensis
sp. nov.
, as described below, the 1-segmented palpus (supposedly indicative of
Asycampta
) occurs in combination with unidentate claws (supposedly indicative of
Pseudocamptomyia
). Also, vein
CuA
of
A
.
karkloofensis
sp. nov.
extends to the wing margin, which matches the condition found in
P
.
phosphila
, but not the situation in
P
.
africana
, in which vein
CuA
is evanescent apically. Likewise, in
Asycampta umngeni
sp. nov.
the presence of a 4-segmented palpus and unidentate claws (both supposedly indicative of
Pseudocamptomyia
) are associated with a vein
CuA
that extends to the wing margin and forms a fork with vein
M
4
(whereas
M
4
is purportedly absent in both
Asycampta
and
Pseudocamptomyia
). There are basically two different options to resolve the conflict between the subgeneric definitions proposed by
Mamaev & Zaitzev (1997)
: on the one hand,
Asycampta
and
Pseudocamptomyia
are maintained as separate subgenera/genera and then need to be defined more precisely, on the other, both names are considered as synonyms.
The situation becomes more complex with the inclusion of
Zadbimyia
Jaschhof & Jaschhof
, a genus described from
Costa Rica
several years after the publication of
Mamaev & Zaitzev’s (1997)
paper (
Jaschhof & Jaschhof 2014
). While
Zadbimyia
is variable regarding the characters discussed above (
Jaschhof & Jaschhof 2014
, fig. 2), the basic construction of male terminalia structures is stable (
Jaschhof & Jaschhof 2014
, fig. 4) and resembles that described here for three new species of
Asycampta
. This finding challenges the distinctness of
Zadbimyia
and
Pseudocamptomyia
(now including
Asycampta
) as postulated by
Jaschhof & Jaschhof (2014)
. The decision here to maintain all three genera as discrete, rather than to subsume both
Asycampta
and
Zadbimyia
under a broad concept of
Pseudocamptomyia
, is backed by male morphological indicators (see below under B). As a further argument, at least
Asycampta
and
Pseudocamptomyia
+
Zadbimyia
likely have long, independent evolutionary histories that began with the separation of South America and Africa some 130 MYA. The sister group relationship postulated here for
Pseudocamptomyia
and
Zadbimyia
cannot be justified by synapomorphies, also because the states of several characters in
Pseudocamptomyia
are beyond judgement (see below). The morphology of
Zadbimyia
is, compared with
Pseudocamptomyia
, in many respects more advanced and largely similar to that of
Asycampta
.
At this point
Larimyia
Fedotova & Sidorenko
must be mentioned, a monotypic genus of
Asynaptini
occurring in the eastern Palearctic Region, the wing and terminalia of which (
Fedotova & Sidorenko 2007
, figs 84, 93) are reminiscent of the genera under discussion here. The original description does not, however, provide sufficient detail to permit any conclusions regarding the systematic position of
Larimyia
.
(B) Definitions.The
Pseudocamptomyia
groupofgenera(synapomorphiesunderlined):
Asycampta
,
Pseudocamptomyia
and
Zadbimyia
form a generic group that differs from other
Asynaptini
in the following combination of male character states (females and larvae are unknown): the scape has a medial cluster of dense setae; the scutum lacks transparent windows; vein
M
1+2
is always and vein
M
4
usually absent; the gonostylus lacks a pectinate tooth; the parameres are merged medially to form the tegmen that is closely tied to the apex of the phallapodeme (only two species of
Zadbimyia
, the affiliation of which is disputable, have separate parameres); the structural complex made of tegmen and phallapodeme is equipped with processes and lobes of varying size, shape and orientation.
Asycampta
. Flagellomeral necks lack microtrichia; circumfila are irregularly, strongly looped. Both labellum and palpus are atrophied; the palpus, which is markedly shorter than the head height, has one to four setaebearing segments. Basitarsal spines are present. The gonostylar apex is either unmodified, equipped with a bunch of large microtrichia (spines), or reinforced by strong sclerotization and then without microtrichia. The geographical distribution is exclusively Afrotropical. The definition given here differs from that by
Mamaev & Zaitzev (1997)
for it emphasizes the distinctions separating
Asycampta
from both
Zadbimyia
and
Pseudocamptomyia
.
Zadbimyia
. Flagellomeral necks are, in most of the species, partly or entirely microtrichose; circumfila are irregularly, strongly looped. Both labellum and palpus are atrophied; the palpus, which is markedly shorter than the head height, has one to four setae-bearing segments. Basitarsal spines are present. The gonostylar apex is variously, densely microtrichose, with conspicuously large microtrichae (spines) being absent. The geographical distribution is exclusively Neotropical.
Pseudocamptomyia
. Flagellomeral necks lack microtrichia; circumfila are slightly sinuous. The palpus has four setae-bearing segments; its length, as well as the structure of the labella, are unknown, due to the poor condition of available specimens. Basitarsi have a microtrichose apical projection rather than a spine. The gonostylar apex is possibly equipped with one or several small spines, which cannot be decided from existing specimens. The geographical distribution is exclusively Nearctic.
(C) Discussion. Besides
Asynapta
and
Camptomyia
, the
Pseudocamptomyia
group of genera represents a further extraordinarily speciose and complex subset of
Asynaptini
. One of the included genera,
Zadbimyia
, is remarkable for its regional and local diversity, with 47 species, both named and unnamed, known to be present in
Costa Rica
, including 35 species known to occur at a single site of cloud forest (
Jaschhof & Jaschhof 2014
; unpublished data). The fact that the genus has not yet been found outside
Costa Rica
is certainly due to the shortage of surveys targeting
Porricondylinae
in the Neotropics. There is every indication that
Asycampta
plays a similar role in the Afrotropics. The three species described here as new were found co-occurring at a single site, and
en passant
rather than through targeted search. The same is true for the two species (including
A
.
africana
(Mamaev & Zaitzev)
comb. nov.
) described from
Somalia
. As a further indication of
Asycampta
’s diversity, the five species now known of the genus exhibit great morphological complexity, which is comparable to that found in
Zadbimyia
. A number of issues regarding the
Pseudocamptomyia
group remain unresolved for the time being. It remains to be shown, for example, whether
Pseudocamptomyia
is exclusively Nearctic in distribution and as poor in species as present data suggest; whether
Larimyia
is a representative and if so the
only
representative of this genus-group in the Palearctic Region; whether
Asycampta
expands into the Oriental Region or whether the
Pseudocamptomyia
group has a different, yet unknown branch in that part of the world. It is obvious that the phylogenetic and biogeographic relations within the
Pseudocamptomyia
group remain as vague as those within the
Asynaptini
as a whole (
Jaschhof & Jaschhof 2013
). The single most important impediment to a better understanding of asynaptine inter-relationships is the shortage of basic taxonomic information regarding nonEuropean faunas.
(D) Identification of
Asycampta
using male morphology. With only five species known at the present, certain nonterminalia characters suffice for their differentiation (
Mamaev & Zaitzev 1997
). Those characters may, to a large extent, be observed even in specimens stored in ethanol, meaning they are more readily accessible compared to terminalia characters, which require investigation by light microscopy. Considering the expectation that dozens of
Asycampta
species
remain to be discovered and described, the specific diagnoses given below give major weight to terminalia structures, which in speciose genera of
Asynaptini
are proven to provide the only positive interspecific distinctions (
e.g.
,
Jaschhof & Jaschhof 2013
,
2014
).