Microlepidoptera new to the British Isles found in the South-west of
England in the last three years.
Bob Heckford
For the purpose of this note the term Microlepidoptera covers all those families which
are not included in Bernard Skinner's Colour Identification Guide to Moths of the British
Isles. The number of Microlepidoptera that have been recorded from the British Isles is
in the region of 1570.
In the last three years about 10 species have been added to the British list, three of
which are migrants or adventives. Three others have been found in the South-west of
England. These are: Ectoedemia caradjai (Nepticulidae), Infurcitinea captans
(Tineidae) and Metalampra italica (Oecophoridae). Infurcitinea captans is certainly a
long term resident but Ectoedemia caradjai may be a recent arrival. Metalampra
italica, which until now was believed to be endemic to Italy, may be an accidental
introduction.
Ectoedemia caradjai (Groschke, 1944)
The Nepticulidae comprise the smallest species of the Lepidoptera, with the
wingspans of British species ranging between 3 and 9 mm. All known larvae feed
internally either within leaves, the buds and keys of some Acer species or just under
the bark of certain trees or plants. These feedings are known as mines and the mines
of many species are sufficiently
distinct to enable identification to be
made on these alone. Indeed this is a
family where species records are more
often made this way than on the
adults,
which are
not
often
encountered.
The larvae of several species of
Nepticulidae make mines in oak
leaves, all on the upper surface. Those
in the genus Stigmella make linear
mines
throughout;
those
in
Ectoedemia start as linear but then
become blotch mines. The larvae of all
known British Ectoedemia mining oak leaves are yellowish or whitish. Between 28
August and 5 September 2004, I found a number of mines, some tenanted and some
vacated, in Quercus petraea in South Devon. These mines were clearly different
because they were generally larger than the mines of other British species and most
importantly the larvae were a distinct emerald green.
Reference to continental literature showed that they were Ectoedemia caradjai,
previously unknown from the British Isles. Although it has been found on Quercus
petraea, the main foodplant in continental Europe is Quercus pubescens, which is not
native to the British Isles.
As a result of this discovery, photographs of the mines were displayed on the national
leaf mining web-site but so far the species has not been found anywhere else either in
Devon or the British Isles. The larval mines are quite distinctive and unlikely to have
been overlooked in the past so it seems possible that it may be a recent arrival, but it
might be a long term, overlooked, resident species restricted to a small area. Hitherto
in western Europe it had not recorded north of the departments of Corrèze and the
Dordogne, France.
Infurcitinea captans Gozmány, 1960
During three evenings in late July 2002 I saw over 60 specimens of an Infurcitinea
species in six separate areas in West Cornwall (V.C. 1), although five of these were
within a 1.5 km length of part of the north coast, the other being on the west coast on the
Lizard peninsula. All the localities are Maritime Heath, being predominately Erica
cinerea L. and Ulex gallii Planch., with patches of Genista pilosa L.
I. captans
I. albicomella
The flight period was between 20.45 and about 21.45 hours. The moths all flew or
‘jumped’ a very short distance, usually less than about 10 cm, and most occurred
amongst the matted plants growing in clumps amongst bare soil/stones, which seemed
to suggest that this was an important part of their microhabitat.
Examination of random samples showed that most of the moths were in good condition,
although not completely fresh.
A few voucher specimens were retained and initially these were recorded, and
published, as Infurcitinea albicomella (Herrich-Schäffer, 1851). This is a rare
species in the British Isles, having been recorded from only four localities. It had
seemed a long lost species at the time that the late E. C. Pelham-Clinton wrote the text
for the Tineidae for Volume 2 of The Moths and Butterflies of Great Britain and
Ireland, published in 1985. He could find only two twentieth century records, one
from Black Hall Rocks, Durham and the other from Torquay, Devon, published in
1912 and 1924 respectively. The only other records were from Howth, Dublin, Ireland
and Morecombe, Lancashire, both from the nineteenth century. All localities were
coastal.
I. albicomella was not seen again in the British Isles until I found it fairly commonly
in a small area at Torquay in 1990, and the following year discovered larvae (which
were previously unknown) amongst detritus and dead leaves, mainly of Cotoneaster
microphyllus agg., lying on the ground. The species has not been found elsewhere
since in the British Isles.
I had not made genitalia preparations any of the Cornish specimens at the time of
publication of my note. When I had taken I. albicomella at Torquay in 1990 and 1991, I
had made a preparation to confirm identification. In 2002 I had assumed, wrongly, that
it was extremely unlikely that another very similar species would occur about 130 km
away on the opposite coast of the adjoining county. However, subsequent dissection of a
male showed that the Cornish specimens were another species, I. captans, which had not
previously been recorded from the British Isles.
As a result of this misidentification, a rather worn male specimen taken by Mr R. J. B.
Hoare on the Lizard on 6 July 1992 and initially determined as I. albicomella, the only
Cornish record, was re-examined and dissected. It too proved to be I. captans.
As shown by both of the initial misidentifications, macroscopically the species is very
similar to I. albicomella, both in markings and wingspan. In series, I. captans appears to
have a slightly narrower forewing and usually a more distinct median fascia, but the
forewing pattern of both species is variable. Both species are clearly separable on the
genitalia.
Biology
In mid April 2003 a colleague, Dr P. H. Sterling of Dorset County Council, and I found
larvae to be locally very common at one of the localities on the north Cornish coast. It
appears that until then the larva was unknown in continental Europe.
Larvae were found on the ground, in silken spinnings amongst black frass, detritus and
dead leaves of Genista pilosa and dead leaves and dead flowers of Erica cinerea.
Although dead leaves and stems of Calluna vulgaris were also on the ground, it may be
significant that no larvae were found amongst those, even in areas where Erica cinerea
and Calluna vulgaris grew next to each other resulting in the dead parts of both lying on
the ground together. This is possibly because dead parts of Calluna vulgaris seem to
retain moisture more and so seemed damper than dead parts of the other plants.
The places where the larvae occurred were either where the plants grew on, or very near,
bare soil or where the vegetation was sparse immediately below Genista pilosa and
Erica cinerea.
Distribution
Because the species resembles I. albicomella, I re-examined such British specimens that
I could trace of that species which all in The Natural History Museum, London. All
appear to be I. albicomella, and one, from Howth, definitely is because it has been
dissected.
Therefore at the present time in the British Isles, I. captans is so far known only from
one place on the Lizard peninsula and an area on the north coast of Cornwall. I suspect
that although the species is probably very local, it may occur in other Maritime Heath
areas on the Cornish coast, but whether it will be found in the British Isles outside
Cornwall remains to be seen.
In continental Europe it has been recorded from France (possibly only one locality),
Switzerland, Italy, Austria and Yugoslavia. It is clear from this that the species does
not require a coastal habitat in continental Europe, and so in Cornwall it has
presumably found a niche on the northern edge of its range.
Metalampra italica Baldizzone, 1977
Inspection, on the morning of 17 August 2003, of the moth trap that I occasionally run in
my garden revealed a worn specimen of Metalampra italica, which had not previously
recorded from the British Isles, and hitherto not outside Italy.
The year had seen a significant number of interesting immigrant species recorded in the
British Isles, but I think that it is more likely that the specimen came from a resident
population.
Another specimen turned up at light in my garden on 7 August 2004, and towards the
end of July that year three specimens were found in and just outside a house at Welwyn,
Hertfordshire. So far no other specimens are known outside Italy.
The species has distinctive markings and does not resemble any other British species.
There is, however, another species, Metalampra cinnamomea, found in continental
Europe which is similar and which occurs in most of western Europe, such as France,
Belgium, Holland and Denmark, and which would seem more likely to be found in this
country, but so far has not.
The larvae of many of the Oecophoridae feed under the dead bark of various trees. The
biology of M. italica is little known; it has been reared accidentally once in Italy from
dead oak collected by a Coleopterist, but the larva was not observed.
Members of the family are not known to be migrants, and so, assuming that thespecimen
reared in Italy had been feeding in the dead wood and not simply pupated there after
feeding somewhere else, it
seems unlikely that the species
has been accidentally introduced
with the garden centre trade
industry (which has been
responsible
for
various
microlepidoptera introductions
including a species on garden
conifers from North America).
The chances of someone
bringing back dead wood from
Italy and introducing it that way
also
seem
implausible.
Therefore either it is a long term
resident occurring at low density
or just possibly somehow imported with logs or trees in the timber trade.
Conclusions
Cornwall already had three resident species of microlepidoptera which have so far not
been found elsewhere in the British Isles, all restricted to either the north coast or the
Lizard peninsula, which are Phyllonorycter staintoniella (Nicelli, 1853) (Gracillariidae),
Syncopacma suecicella (Wolff, 1958) (Gelechiidae) and Agonopterix kuznetzovi
Lvovsky, 1983 (Oecophoridae). The foodplants of the first two, which were only found
in the last 25 years, are Genista pilosa and that of A. kuznetzovi is Serratula tinctoria.
Infurcitinea captans is now added to these. Devon did not have the same distinction, but
now has one species which is so far known only from the county, and shares with
Hertfordshire in having a species otherwise known only from Italy.
As I hope this note shows, there is still much to learn about the peninsula's fauna.
Acknowledgements
I am very grateful to Peter Smithers for photographing the adults and Ian Thirlwell of
Hampshire for allowing me to reproduce the photograph which he took of one of the
mines of Ectoedemia caradjai, with a larva, which I found.
67 Newnham Road, Plympton, Plymouth, Devon PL7 4AW