Towards identification of the scale insects (Hemiptera: Coccomorpha) of continental Africa: 2. Checklists and keys to six archaeococcoid families
Author
Watson, Gillian W.
text
Zootaxa
2022
2022-03-04
5105
3
301
356
journal article
20341
10.11646/zootaxa.5105.3.1
797fca93-60bf-40ce-bb55-e5cb695f6356
1175-5326
6332761
187B04D7-4C35-4E27-9B2D-A616BF59F380
Family
MONOPHLEBIDAE Signoret
Common names:
Giant scales or monophlebids.
Background:
The family
Monophlebidae
used to be regarded as a subfamily of the
Margarodidae
(
sensu lato
) (
Morrison 1928
). The splitting of
Margarodidae
sensu lato
into 11 families by
Hodgson and Foldi (2006)
, based on male morphology, resulted in the monophlebids becoming a separate family of 47 genera containing 265 described species. The family is morphologically very diverse, with four tribes recognized: Llaveiini (all
New World
genera),
Drosichini
,
Iceryini
and
Monophlebini
. Monophlebid females are large, but the cuticle is very delicate, making them very difficult to collect and slide-mount without damage. Live specimens should be killed and preserved in alcohol without any attempt to detach them from the plant material, to avoid tearing the cuticle and losing the mouthparts (
Sirisena
et al.
2013
).
Appearance in life:
Found on plant stems, branches, or leaves, often on woody hosts. Body of adult female normally oval and relatively large, up to
10 mm
long or more (
Aspidoproctus maximus
can reach
35 mm
long); usually with white / yellow / brown wax secretions, these often flocculent, but occasionally without visible wax covering the body; sometimes with waxy projections from the body margins. To protect the eggs, some species form a large, sculptured white ovisac beneath and behind the abdomen, or develop a hollow marsupium by indentation of the venter of the abdomen. Antennae and legs well developed and heavily sclerotized, dark brown; antennae each with 9‒11 segments; legs all similar in size (
Miller
et al.
(2014))
.
Identification:
The best specimens for identification are young adult females just after the final moult, before the body has become distended with developing eggs. It is sometimes possible to identify intermediate-stage females (
Morrison (1928)
provided some keys). Slide-mounted adult female up to
10 mm
long or more, usually broadly oval (
Figs 9
and
10
). Limbs well developed, usually conspicuous and dark; antennae each with 7‒11 segments; legs large, all similar in size, each tarsus 1 segmented; claw digitules not reaching to tip of claw and usually not enlarged apically. Internal anal tube present, the inner end with a simple sclerotized ring with or without pores. Cicatrices present. Abdominal spiracles numbering 1‒8 pairs, usually relatively conspicuous; thoracic spiracles each without pores in atrium (but pores often present just outside spiracular opening) (
Miller
et al.
(2014))
.
Economic importance:
Heavy infestations of monophlebids extract large volumes of phloem sap, drying plant tissues and causing leaf drop and branch dieback. Fouling of plant surfaces with sugary honeydew waste and the resultant sooty mould growth makes the plants unsightly and blocks light and air from the leaves, reducing photosynthesis and plant vigour, productivity and the market value of produce (
Kondo & Watson
2022
in press). The honeydew often attracts attendant ants. In
India
and neighboring areas,
Drosicha mangiferae
Green
and
D. stebbingii
(Stebbing)
(tribe
Drosichini
) are pests of mango (
Karar
et al.
2008
). Some
Icerya
species
are widespread pests, and in some parts of the world predators and dipteran parasites have been introduced to control them, e.g., cottony cushion scale,
Icerya purchasi
Maskell
, is parasitised by
Cryptochaetum iceryi
(Williston)
(
Diptera
:
Cryptochaetidae
), and
I. aegyptiaca
is preyed on by
Novius cardinalis
(Mulsant)
and
N. pumila
(Weise)
(
Coleoptera
:
Coccinellidae
) (
Kondo & Watson
2022
in press).
Biology:
Monophlebids occur on many host-plant species, mostly woody shrubs and trees. There are 1‒3 generations annually, depending on climatic conditions. Usually, the female has four developmental instars; there is no cyst stage. The male has five instars; unlike in most scale insect families, the male prepupa is quite mobile, with well-developed legs and antennae. In
India
,
D. mangiferae
has one generation per year. The eggs, laid in ovisacs in the soil or leaf litter around the host plant, diapause through the winter and hatch early in spring. The crawlers walk up the host plant to the leaves to feed and moult; the sexes are indistinguishable until the third instar. In the male, the prepupa has wing buds and wanders about before forming a waxy test, where it completes development. Adults appear in late spring and mate on the host plant before the females migrate down to the ground to produce ovisacs and eggs (
Karar
et al.
2008
).
Icerya purchasi
, which is present in Africa, has a similar life cycle but remains on the plant throughout; the adult “female” (which is a hermaphrodite that can self-fertilise) lays eggs into a fluted wax ovisac attached to both the body and the substrate. Males are rare; they mate with females, but it is not clear whether their sperm are used for reproduction. Inseminated eggs produce hermaphrodites and unfertilised eggs produce males (
Hughes-Schrader 1930
,
1963
;
Normark 2003
;
Mongue
et al.
2021
).
FIGURE 9.
Monophlebidae
:
Iceryini
, adult female anatomy, from Unruh &
Gullan (2007: 14
, Fig. 1), © Magnolia Press, www. mapress.com/j/zt, reproduced with the copyright holder’s permission.
FIGURE 10.
Icerya seychellarum
Westwood
, adult female, from
Williams & Watson (1990: 24
, Fig. 5), reproduced with permission of the authors and CABI.
Checklist and distributions of
Monophlebidae
in continental Africa
(3 tribes, 13 genera, 71 species, based on
García Morales
et al.
2016
;
Gavrilov-Zimin & Stekolshikov 2018
, and Watson
et al
. 2021).
Tribe
Drosichini
(1 genus, 1 species)
Afrodrosicha nimbae
Vayssière
:
Guinea
Tribe
Iceryini
(5 genera, 29 species)
“
Crypticerya
”
aegyptiensis
Foldi:
Egypt
“
Crypticerya
”
marocensis
Foldi:
Morocco
“
Crypticerya
”
thibaudi
Foldi:
Egypt
“
Crypticerya
” sp. (
sensu
Foldi 2010
); undescribed, on
Rosa
):
Kenya
Gigantococcus alboluteus
(Cockerell)
:
Nigeria
Gigantococcus bicolor
(Newstead)
:
Ghana
Gigantococcus bimaculatus
(De Lotto)
:
Kenya
Gigantococcus brachystegiae
(Hall)
:
Zimbabwe
Gigantococcus cajani
(Newstead)
:
Nigeria
Gigantococcus caudatus
(Newstead)
:
Sierra Leone
,
Uganda
Gigantococcus euphorbiae
(Brain)
:
Benin
,
Mozambique
,
South Africa
,
Zimbabwe
Gigantococcus ewarti
(Newstead)
:
Nigeria
Gigantococcus gowdeyi
(Newstead)
:
Ghana
,
Uganda
Gigantococcus longisetosus
(Newstead)
:
Democratic Republic of the Congo
,
Kenya
,
Sierra Leone
,
Tanzania
Gigantococcus maximus
(Newstead)
:
Democratic Republic of the Congo
,
Gabon
,
Ghana
,
Ivory Coast
,
Kenya
,
Nigeria
,
Uganda
Gigantococcus nigroareolatus
(Newstead)
;
Benin
,
Democratic Republic of the Congo
,
Ghana
,
Tanzania
,
Uganda
Gigantococcus pattersoni
(Newstead)
:
Ghana
,
Kenya
Gigantococcus rodriguezi
(Castel-Branco)
:
Mozambique
Gigantococcus schoutedeni
(Vayssière)
:
Democratic Republic of the Congo
,
Kenya
,
Senegal
Gigantococcus splendidus
(Lindinger)
:
Tanzania
Gigantococcus sulfureus
(Linidinger)
:
Tanzania
,
Uganda
Gigantococcus theobromae
(Newstead)
:
Nigeria
Gueriniella serratulae
(Fabricius)
:
Algeria
Icerya aegyptiaca
(Douglas)
:
Egypt
,
Kenya
,
Tanzania
(
Zanzibar
)
Icerya corticalis
Vayssière
:
Democratic Republic of the Congo
Icerya natalensis
(Douglas)
:
South Africa
Icerya purchasi
Maskell
:
Algeria
,
Angola
,
Democratic Republic of the Congo
,
Egypt
,
Eritrea
,
Ethiopia
,
Kenya
,
Libya
,
Malawi
,
Morocco
,
Mozambique
,
Senegal
,
Somalia
,
South Africa
,
Sudan
,
Tanzania
(including
Zanzibar
),
Togo
,
Tunisia
,
Uganda
,
Zambia
,
Zimbabwe
Icerya seychellarum
(Westwood)
:
Egypt
,
Ethiopia
,
Kenya
,
Malawi
,
South Africa
,
Uganda
“
Steatococcus
” hystrix
Gavrilov-Zimin & Stekolshikov:
Mali
Tribe
Monophlebini
(7 genera, 41 species)
Aspidoproctus armatus
Newstead
:
Democratic Republic of the Congo
,
Mozambique
,
Tanzania
,
Zimbabwe
Aspidoproctus bifurcatus
Thorpe
:
Tanzania
,
Zimbabwe
Aspidoproctus bouvieri
Vayssière
:
Gabon
Aspidoproctus carinatus
(Lindinger)
:
Tanzania
Aspidoproctus congolensis
Vayssière
:
Democratic Republic of the Congo
Aspidoproctus ellenbergeri
Vayssière
:
Zambia
Aspidoproctus ghesquierei
Vayssière
:
Democratic Republic of the Congo
Aspidoproctus giganteus
Newstead
:
Nigeria
Aspidoproctus glaber
(Lindinger)
;
Malawi
,
Zimbabwe
Aspidoproctus magnicornis
Thorpe
:
Uganda
Aspidoproctus maximus
(Lounsbury)
:
Tanzania
,
Zimbabwe
Aspidoproctus mimeuri
Vayssière
:
Senegal
Aspidoproctus mirabilis
(Cockerell)
:
South Africa
,
Tanzania
Aspidoproctus neavei
Newstead
:
Malawi
Aspidoproctus pallidus
(Newstead)
:
Tanzania
Aspidoproctus parvus
(Lindinger)
:
Tanzania
Aspidoproctus pertinax
(Newstead)
:
Malawi
,
Zimbabwe
Aspidoproctus tricornis
(Newstead)
:
Kenya
,
Malawi
,
South Africa
,
Zimbabwe
Aspidoproctus verrucosus
Newstead
;
Uganda
Aspidoproctus vuileti
(Vayssière)
:
Niger
Aspidoproctus zimmermanni
(Newstead)
,
comb. n.
(see below):
Tanzania
Monophleboides africanus
(Newstead)
:
Namibia
Monophleboides arachidis
Vayssière
:
Democratic Republic of the Congo
Monophleboides gymnocarpi
(Hall)
:
Egypt
Monophleboides hirtus
(Brain)
:
Malawi
,
South Africa
Monophleboides sjostedti
(Newstead)
:
Tanzania
Monophleboides suaedae halocnemae
(Vayssière)
:
Tunisia
Monophleboides suaedae suaedae
(Vayssière)
:
Tunisia
Monophlebus dumonti
Vayssière
:
Tunisia
Monophlebus hoggarensis
Vayssière
;
Algeria
Monophlebus raddoni
Westwood
:
Ghana
,
Uganda
Palaeococcus fuscipennis
(Burmeister)
:
Algeria
Pseudaspidoproctus acaciae
(Joubert)
:
South Africa
Pseudaspidoproctus africanus
(Newstead)
:
Tanzania
Pseudaspidoproctus fortis
(Cockerell)
:
South Africa
Pseudaspidoproctus fulleri
(Cockerell)
:
Kenya
,
South Africa
Pseudaspidoproctus hyphaeniacus
(Hall)
:
Egypt
,
Libya
Pseudaspidoproctus vayssieriellus
Ghesquière
:
Democratic Republic of the Congo
,
Nigeria
Vrydagha lepesmei
Vayssière
;
Democratic Republic of the Congo
Walkeriana andreae
Green
:
Democratic Republic of the Congo
Walkeriana digitifrons
Newstead
:
Uganda
Key to most of the known genera of
Monophlebidae
in continental Africa
1(0) Abdominal spiracles numbering 2‒4 pairs (on posterior abdominal segments). Cicatrices numbering 1‒13. Body covered with hairs and flagellate setae................................................................. tribe
Iceryini
... 2
- Abdominal spiracles usually difficult to see, numbering 5‒7 pairs. Cicatrices numbering 1 or 3 or very numerous. Body covered with spines and/or hairs................................................................................ 6
2(1) Abdominal spiracles numbering 4 pairs. Labium long, with 3 segments, the basal segment very narrow. Anal tube inner ring with 2 rows of pores..................................................................
Gueriniella
(
Fig. 11
)
- Abdominal spiracles numbering 2 or 3 pairs. Labium short and conical, with 2 indistinct segments, the basal segment wide. Anal tube inner ring without pores....................................................................... 3
3(2) Ventral cicatrices numbering 6‒23 posterior to vulva, grouped in a circular area on midline........ “
Crypticerya
” (
Fig. 12
)
- Ventral cicatrices numbering 1 or 3 posterior to vulva in a single row across midline................................ 4
4(3) Compound multilocular pores absent. Open-centre pores present or absent...........................
Icerya
(
Fig. 10
)
- Compound multilocular pores present. Open-centre pores absent............................................... 5
5(4) Dorsal setae robust, spiniform and slightly lanceolate, quite crowded; most setae in marginal areas robust, some up to 5x as long as a dorsal seta, crowded. Marsupium present. With 3 cicatrices....................... “
Steatococcus
”
hystrix
(
Fig. 13
)
- Dorsal setae fine and hair-like, not crowded; setae in marginal areas hairlike, sometimes robust and very long but not crowded. Marsupium present or absent. With 1 or 3 cicatrices......................................
Gigantococcus
(
Fig. 14
)
6(1) Body very densely covered with hairs, all same
type
, finely pointed. Antenna usually with 8 or 9 segments.................................................................................. tribe
Drosichini
...
Afrodrosicha
(
Fig. 15
)
- Body with hairs and/or spines, often of more than
1 type
, not crowded over entire surface. Antenna with 8‒11 segments..................................................................................... tribe
Monophlebin
... 7
7(6) Claw with 3 denticles. Multilocular pores of
2 types
, some with large loculi, some with small loculi.
Palaeococcus
(
Fig. 16
)
- Claw without denticles. Multilocular pores of 1 or more
types
................................................. 8
8(7) Ventral cicatrices very numerous on head, thorax and abdomen, forming irregular rows that form a broad submarginal band on each side. Ventral marsupial opening relatively small and subcircular, bordered by a dense band of disc pores. In life, marsupial opening normally covered by a white layer of felted wax...................................
Aspidoproctus
(
Fig. 17
)
- Ventral cicatrices numbering 1 or 3, situated posterior to vulva in a row across midline. Marsupial opening, if present, often U- or V-shaped and bordered by relatively few pores; not covered with felted wax in life............................ 9
9(8) Body margin with about 12 segmental tubercles on each side of thorax and abdomen, each bearing single or small groups of tubular bilocular pores. Body with numerous, conspicuous quadrilocular pores. Dorsum with patches of densely crowded spines..............................................................................
Walkeriana
(
Fig. 18
)
- Body margin without tubular bilocular pores or segmental tubercles. Quadrilocular pores, if present, small and inconspicuous. Dorsum without patches of crowded spines............................................................... 10
10(9) Body with at least a few cylindrical spines. Marsupium present. Ventral cicatrices numbering 3
Pseudaspidoproctus
(
Fig. 19
)
- Body without cylindrical spines. Marsupium absent. Ventral cicatrices numbering 1 or 3........................... 11
11(10) Antenna with 10 segments. Ventral cicatrices numbering 3. Anal tube with internal ring bearing pores....
Vrydagha
(
Fig. 20
)
- Antenna with 11 segments. With 1 or 3 ventral cicatrices. Anal tube without internal ring of pores.................... 11
12(11) Body margin with large tubular bilocular pores.........................................
Monophleboides
(
Fig. 21
)
- Body margin without large tubular bilocular pores.................................................
Monophlebus