Observations on the Biology of Afrotropical Hesperiidae (Lepidoptera). Part 5. Hesperiinae incertae sedis: Dicotyledon Feeders
Author
Cock, Matthew J. W.
C / o CABI Europe - UK, Bakeham Lane, Egham, TW 20 9 TY, UK (e-mail: m. cock @ cabi. org; mjwcock @ btinternet. com)
m.cock@cabi.org
Author
Congdon, Colin E.
African Butterfly Research Institute (ABRI), P. O. Box 14308, Nairobi, Kenya (e-mail: colin. congdon @ gmail. com)
colin.congdon@gmail.com
text
Zootaxa
2013
2013-10-25
3724
1
1
85
http://dx.doi.org/10.11646/zootaxa.3724.1.1
journal article
134452
10.11646/zootaxa.3724.1.1
3fe084ed-d367-4d5a-9ed0-48882760ba96
1175-5326
5267833
7D05BB2E-4373-4AFB-8DD3-ABE203D3BEC1
Platylesches
Holland
, 1896
This is a genus of at least 20 species, which is restricted to sub-Saharan Africa, and is in need of revision (
Larsen 2005
). Early last century, Dollman (unpublished) reared
Pl. moritili
from
Parinari curatellifolia
(
Chrysobalanaceae
,
Malpighiales
) in
Zambia
, but this record was never published. The
Chrysobalanaceae
food plants were only rediscovered in the last 30 years. All known food plants are in the
Chrysobalanaceae
, and the great majority of records are from
Parinari
spp.
Parinari curatellifolia
is a large spreading tree up to
13m
, characteristic of sandy soils and open deciduous woodland and is seldom cut down as its fruit (mbolola plum) is valued by local people (
Palgrave 1983
). It is found through tropical Africa (
National Research Council 2008
) to south-west
Kenya
(
Beentje 1994
) and south to northern
South Africa
(
Palgrave 1983
).
Maranthes floribunda
is a tree of Zambezian woodland (
White
et al
. 2001
) that can easily be confused with
Pa. curatellifolia
.
Parinari excelsa
, is a tree associated with forests through West Africa, east to
Tanzania
(not
Kenya
) and south to
Mozambique
, as well as
South Africa
(
White 1978
), and is used as a food plant by
Pl. galesa
. A third species occurring mainly in southern Africa is the low growing (suffrutex)
Pa. capensis
, found in sandy areas (
Palgrave 1983
), which in suitable habitat can be found as far north as the Mpanda and
Tabora
Regions of western
Tanzania
(K. Vollesen, pers. comm., 2013). Recently
M. goetzeniana
was found abundantly in Mabu forest in Northern
Mozambique
—it was previously thought to be an Usambara endemic. Other species of
Maranthes
occur in West Africa—one having been recorded as a food plant of
Platylesches
in
Côte d’Ivoire
(
Vuattoux 1999
). Other species of
Parinari
and
Maranthes
are likely to be food plants. In addition to the eight species of
Platylesches
we have documented below, two other species are known to feed on
Chrysobalanaceae
, and
Pl. dolomitica
Henning & Henning, 1997
, which is considered ‘vulnerable’ in
Gauteng Province
,
South Africa
, is suspected to feed on
Pa. capensis
(
Woodhall 2005
,
Henning
et al
. 2009
).
There are no food plant records from other plant taxa, except for an early record from
South Africa
of
Pl. galesa
feeding on
Ehrharta erecta
and other grasses (
Murray 1959
), which has been repeated in the subsequent literature (
Dickson & Kroon 1978
,
Kielland 1990
,
Larsen 1991
,
Ackery
et al
. 1995
). However, in light of more recent records from
Parinari
spp.
, grasses are now considered doubtful (
Heath
et al
. 2002
) or incorrect (
Larsen 2005
,
Woodhall 2005
). We agree that all records of grasses as food plants should be discounted.
In this series of papers, we have followed the leaf shelter classification and terminology of
Greeney & Jones (2003)
and
Greeney (2009)
, summarised in
Cock (2010)
, which is based on shelter construction, particularly the number of main cuts used to make a shelter.
Congdon
et al
. (2008)
also considered this question, and adopted a functional approach to the classification of leaf shelters, summarised in
Cock & Congdon (2011a)
. This functional classification is especially relevant to the genus
Platylesches
, and so is presented here again.
Tube or tubular shelters
. The caterpillar folds or rolls a leaf, and eats the leaf from the apex back towards the base, extending the shelter backwards as it goes. When it reaches the base of the leaf it moves to a new one and repeats the process until fully fed. Some species of
Hesperiinae
which feed on dicotyledons do this, including some
Platylesches
spp.
These
Platylesches
spp.
and the
Andronymus
spp.
treated above feed on flush leaves near the growing point of the plant, completing development quickly before the leaves harden. The following tube shelter builders are treated below:
Pl. galesa
,
Pl. moritili
,
Pl. neba
and
Pl. picanini
.
Chamber shelters.
The caterpillar makes a more or less permanent shelter often in more mature foliage, coming out primarily at night to feed, and returning to the chamber during the day. The caterpillar only makes a new shelter when it outgrows the old one, or when the food source becomes too distant. Most Pyrginae do this (
Cock 2010
,
Cock & Congdon 2011a
, b) and so do some
Platylesches
spp.
These species usually develop more slowly, perhaps because mature foliage is less nutritious. A rearing container containing a single tube species
Platylesches
caterpillar will contain more frass in the morning than a container of a dozen chamber species caterpillars. Of the
Platylesches
spp.
whose biology is now known, the following are chamber makers:
Pl. ayresii
,
Pl. langa
,
Pl robustus
,
Pl. shona
and
Pl. tina
.
In TCEC’s experience, the tube-making
Platylesches
spp.
do not pupate in their shelters, and he has not found their pupae in the wild. If the caterpillars are sleeved out, pupae are found amongst leaf litter in the bottom of the bag or in silk lined cocoons in folds of the bag near the bottom, suggesting that they would normally pupate in litter on the ground. In captivity, the old tubes might constitute leaf litter and be incorporated into a pupation chamber, but caterpillars often pupate under leaves on the bottom of the box. Chamber-making
Platylesches
spp.
, on the other hand, invariably pupate in their shelters, closing the shelter entrances with a circle of elongate triangular flaps (
Figures 64.2
and
68.2
) or loose threads (
Pl. shona
).
TCEC has reared a further three
Platylesches
spp.
from tube shelters on
Pa. curatellifolia
in
Tanzania
, which belong to the group which includes
Pl. iva
Evans, 1937
and
Pl
.
affinissima
Strand, 1920
.
Platylesches iva
is known from
Ivory Coast
through
Nigeria
to
Uganda
,
Malawi
and
Tanzania
, where it is reported from a single butterfly from Dendene Forest, south of
Dar es Salaam
, although
Larsen (2005)
doubts the identity of this specimen.
Platylesches affinissima
is known from West Africa to
Malawi
,
Mozambique
and
Zimbabwe
; in
Tanzania
it is a western butterfly, with a possible record from the Uluguru Mountains in the east. These caterpillars are rare in TCEC’s experience, and the three raised appear not to agree exactly with either of the two named species. This material, including adults, was documented in
Congdon
et al
. (2008)
and repeated here for completeness.
Figures 62.1 and 62.2
were each reared once. The narrow head of
Figures 62.2
and
6
is unlike any other
Platylesches
sp.
and we do not believe it can represent the same species as
Figure 62.1
, yet the adults both come closest to
Pl. affinissima
, although that of
Figure 62.2
is small.
Figures 62.3–4
show another species reared twice, the adults of which are close to
Pl. iva
. The taxonomy of these specimens has yet to be resolved, but will be addressed in T.B. Larsen’s revision of the Afrotropical
Hesperiidae
, or in an anticipated addendum part to the present series.