Systematics, revisionary taxonomy, and biodiversity of Afrotropical Lithocolletinae (Lepidoptera: Gracillariidae)
Author
Prins, Jurate De
Author
Kawahara, Akito Y.
text
Zootaxa
2012
2012-12-20
3594
1
1
283
http://dx.doi.org/10.11646/zootaxa.3594.1.1
journal article
20704
10.11646/zootaxa.3594.1.1
79af20a5-77f9-4240-ac45-e27fab775ca1
11755334
6052126
B00799F3-F397-438C-B1E1-A8440E636921
The
loxozona
group
The forewing pattern in the
loxozona
group resembles very closely that of the majority of Afrotropical
Phyllonorycter
species.
Larvae of the
loxozona
group feed on
Dombeya
spp.
[
Malvaceae
]. Developed mines appear to resemble gall-like swellings.
The
loxozona
group consists of three species:
P. didymopa
(
Vári, 1961
)
,
P. loxozona
(
Meyrick, 1936
)
, and
P. madagascariensis
(
Viette, 1949
)
.
Phyllonorycter madagascariensis
was described from a single specimen without abdomen by
Viette (1949)
. We made all possible efforts to find the holotype of
P. madagascariensis
(see
Remarks
below). A neotype designation is very much anticipated. We believe that with the kind help of the lepidopterists’ community it will be possible in the near future to obtain a neotype of this species reared from
Dombeya spectabilis
which grows in the Botanical Garden of Tsimbazaza, Antananarivo, Madagascar (type locality of
P. madagascariensis
). Based on the original description, the forewing pattern of
P. madagascariensis
resembles that of
P. didymopa
. All three species make a long, semi-transparent gallery during the development of early instars and feed on
Dombeya
ssp. [
Malvaceae
] (
P. didymopa
feeds on
D. rotundifolia
,
P. loxozona
on
D. emarginata
and
D. rotundifolia
, and
P. madagascariensis
feeds on
D
.
spectabilis
). We, therefore, tentively included
P. madagascariensis
into this informal species group. Unfortunately, the unavailability of genitalia prevent a proper diagnosis between
P. madagascariensis
,
P. loxozona
and
P. didymopa
.
Male genitalia are known only for
P. loxozona
. They show a few, rather particular set of features characterizing this species: tegumen rather short, tuba analis long, protruding ca. 1/2 length of tegumen, long sinuate narrow valva covered with dense setation on cucullus (similar to
Cameraria
), crescent-shaped vinculum with very short saccus, sternum VIII truncate, strongly tapering caudally with blunt weakly bidentate apex.
Female genitalia of the
loxozona
group, like those of
Cameraria
,
are characterized by the location of ostium bursae opening at posterior margin of segment VII. Antrum in the
loxozona
group is broad and sclerotized, with strongly sclerotized ring encircling the opening of ostium bursae. Ductus bursae in the
loxozona
group like in
Cameraria
(the
hexalobina
and the
landryi
groups) might be crossed by a small plate situated anteriad antrum (in
P. loxozona
). Corpus bursae of the
loxozona
group without signum.
Remarks
.
Vári (1961: 222)
wrote the following: “It is an interesting peculiarity to find a gall-forming species in
Lithocolletis
, as most species make tentiform mines and no special growth of the leaf tissue is induced. A further interesting matter is the presence of the long, semi-transparent gallery, made during the early stages, whereas all other species are sapfeeding during this period, and no semi-transparent galleries are made”. This would indicate that the early instars of this group might possess a slightly different metamorphic development of mouthparts from the rest of
Phyllonorycter
. The male and female genitalia of the
loxozona
group resemble these of
Cameraria
. However such characters, as general pattern of forewing, absence of clearly notable setae on apex of tegumen, strongly developed complete transtilla, put these species close to
Phyllonorycter
. Probably, the
loxozona
group species might require a designation of a new genus. However, it seems preferable at the moment to follow a more conservative approach leaving this species group in
Phyllonorycter
, as initially proposed by
Meyrick (1936: 33)
until detailed larval and pupal morphology is studied and molecular characters are obtained.
Key to the species of
loxozona
group based on external characters and host plants
1. Second fascia at 1/2 of forewing slightly oblique towards apex, broader at dorsum and slightly tapering towards costa, blunt at costa (
Figs 81, 82, 85
).................................................................................. 2
– Second fascia at 1/2 of forewing straight transverse, swelled at dorsal sector and bluntly tapering at costa; larvae feed on
Dombeya emarginata
and
D. rotundifolia
. [
Malvaceae
] (
Figs 83, 84
)....................................40.
loxozona
2. Larvae feed on
D. rotundifolia
[
Malvaceae
]....................................................... 39.
didymopa
– Larvae feed on
D. spectabilis
[
Malvaceae
]................................................. 41.
madagascariensis
Key to females of
loxozona
group based on genitalia*
1. Anterior apophyses only slightly shorter than posterior apophyses; margin of ostium bursae not sclerotized (Fig. 331)................................................................................................. 39. didymopa
– Anterior apophyses more than 2× shorter than posterior apophyses; margin of ostium bursae heavily sclerotized (
Fig. 332
)..............................................................................................40.
loxozona
* female genitalia of
P. madagascariensis
are unknown.