Bulletin of Entomological Research (2014) 104, 164–175
© Cambridge University Press 2013
doi:10.1017/S0007485313000606
Delimitation and description of the
immature stages of a pollinating fig wasp,
Ceratosolen solmsi marchali Mayr
(Hymenoptera: Agaonidae)
Ling-Yi Jia1,2, Jin-Hua Xiao1, Li-Ming Niu3,
Guang-Chang Ma3, Yue-Guan Fu3, Derek W. Dunn4
and Da-Wei Huang1,5*
1
Key Laboratory of Zoological Systematics and Evolution, Institute of
Zoology, Chinese Academy of Sciences, Beijing 100101, China: 2University of
Chinese Academy of Sciences, Beijing, 100039, China: 3Environment and
Plant Protection Institute, Chinese Academy of Tropical Agricultural
Sciences, Danzhou, Hainan, 571737, China: 4School of Biological Sciences,
University of Reading, UK: 5College of Plant Protection, Shandong
Agricultural University, Tai’an, Shandong, 271018, China
Abstract
The mutualism between fig trees and their wasp pollinators is a model system for
many ecological and evolutionary studies. However, the immature stages of pollinating fig wasps have rarely been studied. We monitored developing fig wasps of
known ages and performed a series of dissections at 24 h intervals to identify key
developmental traits of Ceratosolen solmsi marchali Mayr (Hymenoptera: Agaonidae),
a pollinator of Ficus hispida L. (Moraceae). We identified where in the Ficus ovary eggs
were deposited and time to hatch. We were also able to identify the timing and key
underlying characters of five larval instars, three sub-pupal stages, and a single
prepupal stage. We provide detailed morphological descriptions for the key stages
and report some behavioral observations of the wasps in the several developmental
stages we recorded. Scanning electron microscope images were taken.
Keywords: Ceratosolen solmsi marchali, immature stages, morphology
(Accepted 25 October 2013; First published online 29 November 2013)
Introduction
The mutualism between fig trees (Ficus spp.) and their
pollinating wasps is a classic model of coevolution, which has
stimulated much research into the evolution, population
genetics, biogeography, and ecology of the system (Janzen,
1979; Weiblen, 2002; Jandér & Herre, 2010). However, the
biology of the immature stages of the pollinating wasps has
*Author for correspondence
Phone: + 86 010 64807235
Fax: + 86 010 64807235
E-mail: [email protected]
been relatively neglected (Galil & Eisikowitch, 1968a;
Valdeyron & Lloyd, 1979). Even the location of egg deposition
within the Ficus ovary has been revealed only recently by
histological methods (Elias et al., 2012). The lack of information
on the delimitation and description of pollinator larvae
hinders the progress of various aspects of fig wasp research.
Unlike most other wasps, pollinating and non-pollinating
fig wasps are confined in their larval stages to the Ficus
syconium, the enclosed inflorescence characteristic of the
genus (Weiblen, 2002). Pollinating fig wasps induce galls in
Ficus ovaries, with one larva developing in each gall. Because
the Ficus syconium is a closed system, it is not possible to
observe live larvae at any point in time other than through
destructive sampling.
Delimitation and description of the immature stages of a pollinating fig wasp
165
Fig. 1. Ovarian egg and a newly laid egg of C. solmsi marcahli: (A) Reproductive system of an adult female. (B) Inflated calyx and ovariole
tubules after dissection. Calyxes were 401.23 ± 0.02 μm (n = 15) in length. (C) Egg adhering to a gall (4th day post-oviposition). (D) Egg
separated from the Ficus tissue (4th day post-oviposition). Red arrows in C and D indicate cavities at the posterior end of eggs, emerged
during embryo development.
Ficus hispida L. is a functionally dioecious (gynodioecious)
species, in that the male and female reproductive functions are
confined to different trees; seeds develop in the syconia of the
female trees, and pollen (and pollinating wasps) in the syconia
of the male trees. On Hainan Island, the pollinator species of
F. hispida is Ceratosolen somlsi marchali Mayr. Female pollinator
wasps (foundresses) enter a receptive syconium through the
ostiole. When inside the central lumen of the syconium on a
male tree, each foundress deposits her eggs individually into
the ovaries by inserting her ovipositor through the styles,
while simultaneously distributing the pollen that she has carried from her natal tree. The oviposited flowers are induced to
become galls. After oviposition, each offspring grows within
its gall as its natal syconium also grows to maturity, a process
that takes approximately 30 days. Upon maturation, the male
pollinators emerge from their galls first, mate with the females,
and then chew holes in the syconium wall to enable the now
pollen-laden females to disperse to other receptive F. hispida
trees (Yang et al., 2002). Under natural condition, more than
one (often 2 or 3) foundresses oviposit in a single syconium of
F. hispida (Yang et al., 2002). F. hispida trees also harbor three
non-pollinating fig wasp species (Peng et al., 2005). Besides,
there are abundant and diverse fig-associated insects, such as
pulp eating insects (e.g., moths), sap feeders (e.g., aphids),
predators (e.g., ants), and decomposers (e.g., fruit flies). Taken
together with the pollinating fig wasps and non-pollinating
fig wasps, they comprise a complex ecosystem (Yang et al.,
2008).
Lack of knowledge of the immature stages of pollinating
fig wasps hinders progress in a variety of studies, such as
wasp development and clarifying the ecological relationships
between different wasp species. The purpose of this study
was to delimitate and describe the immature stages of a
pollinating fig wasp species, Ceratosolen solmsi marchali,
the pollinator of F. hispida. We did this by monitoring wasp
larvae of known ages over their development from egg
to adult, a process that involved almost 1 month. Our data
enabled us to identify the various key life-cycle stages, and
to provide diagnostic characters of the pupal stage for
both sexes.
Materials and methods
Study system and wasp life cycle
The material used for the study was collected from three
male F. hispida trees (19°30′N, 109°31′E) growing near to
the campus of the Chinese Academy of Tropical Agricultural
Sciences in Danzhou, Hainan Island from June 12 to
September 15.
L.-Y. Jia et al.
166
Fig. 2. Larva and prepupa of C. solmsi marcahli: (A) First-instar larva (5th day post-oviposition). (B) Second-instar larva (10th day postoviposition). (C) Third-instar larva (11th day post-oviposition). (D) Fourth-instar larva (16th day post-oviposition), showing presumed limb
imaginal discs wrapped in each protrusion (blue arrows) and yellowish contents of alimentary tract (red arrow). (E) Fifth-instar larva from
ventral view (19th day post-oviposition), showing lateral and latero-ventral protrusion (blue arrow) and red mouth parts (red arrow).
(F) Prepupa (20th day post-oviposition) resembled the final-instar larva, lateral view, showing swollened mesosomal region of prepupa
(blue arrow). Thirteen body segments (I–XIII) were illustrated in (B, C).
Syconium sampling
Initially, we identified three male F. hispida trees that each
displayed a large crop of pre-receptive syconia (A-phase)
(Galil & Eisikowitch, 1968b). To prevent natural wasp oviposition and the interference of other insect species, we
covered several fig branches with fine-mesh nylon bags,
each displaying several syconia. All branches were inspected
daily until the syconia within each bag showed signs
of receptivity, with the entrance to the ostiole becoming
visible. On detecting receptivity, the bag was removed, and a
single female adult C. solmsi marchali (mated or virgin) that
had been recently collected from a mature syconium of a
nearby tree was placed at the entrance to the ostiole of each
syconium. After wasp introduction, the figs were immediately
re-covered with fine-mesh nylon bags to exclude other
Delimitation and description of the immature stages of a pollinating fig wasp
167
Fig. 3. Third- and fourth-instar larva (A) Mouthparts of third-instar larva (13th day post-oviposition), showing sharply edentate mandibles.
(B) Ventral view of fourth-instar larva (17th day post-oviposition). (C) Enlarged view of mouthparts of fourth-instar larva (md: mandible;
mp: maxillary palp; lp: labial palp). Thirteen body segments (I–XIII) were illustrated in B.
fig wasps and insects. After foundress entrance, we removed
3–6 syconia every 24 h and returned them to the laboratory for
processing and measurement. A total of 521 syconia were
checked. Average of daily maximum and minimum temperature was 34–25 °C, released by the National Meterological
Administration.
Dissection, observation and measurement
Each syconium was dissected by a cross cut of the outside
wall with a scalpel. With the aid of a stereomicroscope (SZ61,
Olympus) and a pair of fine forceps, swollen galls were
removed into a Petri dish containing 0.9% physiological saline.
By the incremental removal of the ovary tissue, the contents of
each gall could be exposed (egg or larva, depending on the age
of the gall since foundress introduction). The ovaries from
adult female wasps were also dissected to examine egg morphology prior to oviposition. Because fig wasp ovaries were
pale and opaque (Dunn et al., 2011), the ovarian tissue was
carmine dyed (Fagerström & Wiklund, 1982). After dissection,
each sample was photographed and measured with a SteREO
Lumar.V12 imaging system (Carl Zeiss) using AxioVision
(Carl Zeiss) image analysis software. Larvae for scanning
electron microscope (SEM) observation were fixed in 4%
glutaraldehyde and stored in 100% ethanol before dried in the
Leica EM CPD300 Critical Point Dryer. They were then affixed
to aluminum SEM stubs adhesive tabs. Stub-mounted specimens were sputter-coated with gold. The specimens were
inspected under a Quanta200 SEM. Measurements recorded
include body length, width, cephalic width, and mandible
length. With respect to the measurements of curve bodies for
certain stages, we measured several short straight parts along
the midline of larval body, and then added them up to
compute the total body length.
Sex identifying of immature C. solmsi marchali
PCRs of sex-specific transcripts of doublesex (dsx), an
important gene in sex determination (Oliveira et al., 2009),
were used to confirm the sexes of larvae as early as 16 days
post-oviposition (unpublished data). The results showed that
all the offspring of virgin females were males, and most offspring of mated females were females (female/total offspring
was 0.89 ± 0.06, n = 9). This was consistent with the previous
reports that in one-foundress figs, offspring sex ratios of
C. solmsi were highly female-biased (Hu et al., 2013). In addition, we did more than 20 sets (30 eggs or larvae per set) of
morphologic comparisons on the eggs and larvae between the
male offspring of virgin females and sex-unknown offspring
of mated females. If there were any significant morphological
difference between two sexes, it would be easily to distinguish.
Results
Eggs within ovaries (fig. 1A, B)
Pollinating fig wasps were proovigenic, with all eggs
mature at eclosion. Approximately 100 eggs were in each calyx
(fig. 1A, B).
Egg body elongate and pale in color (egg body: 111.62 ±
0.41 μm long, range 97.85–123.24 μm; 39.62 ± 0.07 μm wide,
range 37.96–41.77 μm; n = 17), with the posterior end connected to a pedicel (pedicel length: 52.03 ± 0.09 μm, range
48.66–54.43 μm; n = 17).
Eggs post-oviposition (fig. 1C, D)
The youngest eggs we could examine from galls were those
on the second day post-oviposition. The egg was deposited
168
L.-Y. Jia et al.
Fig. 4. Final-instar larva under SEM: (A) Lateral view of fifth-instar larva (19th day post-oviposition). (B) Enlarged view of spiracle, showing
the largest spiracle (spVIII). (C) Enlarged view of mouthparts (md: mandible; mp: maxillary palp; lp: labial palp). Thirteen body segments
(I–XIII) were illustrated in A.
Delimitation and description of the immature stages of a pollinating fig wasp
169
Fig. 5. Ficus ovary and developing C. solmsi marchali larva in situ in a Ficus ovary: (A) Ficus ovaries under light microscope (6th day postoviposition). (B) A dissected Ficus ovary under SEM (6th day post-oviposition). Arrow indicates style. (C) Larva of C. solmsi marchali in situ in
a Ficus ovary, dyed with carmine (13th day post-oviposition).
inside the Ficus ovary with the pedicel attached to the style
where it joined the Ficus ovary.
Egg smooth, without any tubercule or spine. No micropyle
or sculpturing. The shape, color, and general appeared similar
to ovarian eggs, except for the increase in size (body length:
146.67 ± 0.39 μm, range 129.51–164.55 μm; body width: 68.61 ±
0.15 μm, range 61–75.21 μm; pedicel length: 69.19 ± 0.10 μm,
range 64.26–73.42 μm; n = 22). The developing embryo in the
egg migrated to the anterior of the egg, leaving a cavity at the
posterior end (fig. 1C, D).
After 5 days post-oviposition, a few larvae were inside the
Ficus ovary, whereas others remained within eggs, which suggested that neonate larvae emerge about 5 days after
oviposition (4.81 ± 0.02 days, n = 26).
Larval stages
C. solmsi marchali had a typical chalcidiform larva, with a
smooth, weakly sclerotized body surface, without any setae or
tubercle (fig. 2A–F). The labium was not distinguishable.
Mandibles were sclerotized and unidentate. Antennal tubercles were not present (Parker, 1924; Chu & Cutkomp, 1992).
Changes in body form and mondibular structure indicate
five instars prior to pupation. In first instar, the mandibles
were indistinct even using scanning electron microscopy,
width measurements of head capsules were made to check the
instar delimitation. Exuviae from third and fourth instars that
were casually found attached to larvae helped confirm the
instars. We were not able to determine the precise timing of
every larval instar by monitoring molting, because the larvae
were often embedded in fragments of the Ficus ovary, which
looked similar to exuviae. Larvae in instars 2–5 all had
cranium and 13 body segments (I: head; II–IV: mesosoma;
V–XIII: metasoma) (figs 2B, C, 3B and 4A).
First-instar larva (figs 2A, 5A, B and 6A)
Length 240.21 ± 2.6 μm, range 143.92–415.29 μm; width
106.90 ± 1.2 μm range 77.21–115.92 μm; n = 26. Head capsule
width 59.10 ± 0.5 μm, range 47.28–76.48 μm, n = 17. Cylindrical
and tapering apically. Translucent with faint body segmentation (figs 2A and 6A). Alimentary tract pale at the end of first
instar. Gut contents gradually obvious as feeding ensued.
Only modest segmental motion, unlike the vigorous firstinstar larva of other hymenopteran species (Jackson, 1966;
Jacas et al., 2009; Gumovsky & Ramadan, 2011). Gall containing first-instar larva was filled with fluid and had a
delicate outer membrane that was easily punctured during
dissection (fig. 5A, B).
Second-instar larva (figs 2B and 6B, C)
Length 519.33 ± 2.9 μm, range 427.54–648.55 μm; width
209.37 ± 1.1 μm, range 162.84–279.65 μm; n = 24. Head capsule
L.-Y. Jia et al.
170
Fig. 6. First- and second-instar larvae under SEM: (A) First-instar larva (6th day post-oviposition), showing the head and faint body
segmentation. (B) Second-instar larva (9th day post-oviposition). (C) Enlarged view of mouthparts of second instar, showing slender
mandibles (md: mandible).
width 124.56 ± 0.7 μm, range 102.16–163.42 μm, n = 21 (fig. 2B).
Translucent, fusiform, and oval in cross-section (figs 2B and
6B). Cranium unsclerotized. Buccal region sclerotized of a
light brown color. Mandibles concealed behind the labrum
and small, slender and not protruding (fig. 6C). Mandible
width 4.39 ± 0.03 μm (n = 6). Mid-gut filled with pale yellowish
granules, occupied almost half of the body length. Larva
sucked the fluid from the Ficus ovary by repeated contraction
of the muscles surrounding its oesophagus.
attenuated posteriorly and more arched, Body grayish white
and less translucent than the larvae in preceding instars. Two
protrusions emerged at the lateral and latero-ventral areas
of the mesosomal segments (II–IV, figs 2C and 3B). Cranium
sclerotized. Mandibles length 52.49 ± 0.1 μm (n = 16), heavily
sclerotized (fig. 3C) and deeper red at the tips (fig. 2D).
Alimentary tract extended and occupied larger area, appeared
yellowish in color (fig. 2D).
Fifth-instar larva (figs 2E and 4)
Third-instar larva (figs 2C, 5C and 3A)
Molting was casually observed with exuviae attaching
to the anal end of larvae after dissected from the Ficus ovary
into physiological saline. Length 1016.77 ± 7.2 μm, range
664.18–1354.93 μm; width 454.26 ± 2.8 μm, range 281.60–
526.89 μm; n = 45. Head capsule width 192.78 ± 0.4 μm, range
173.82–209.49 μm, n = 22. Resembled second instar, except
for the wider mesosomal segments (II–IV). Body wall semitranslucent (fig. 2C). Mandible length 29.19 ± 0.5 μm (n = 12),
curved, with more sclerotized blades and well developed
bases. Sharply edentate mandibles overlapped at the tips
(fig. 3A). Active feeding, mid-gut packed with food filling
almost the whole body (fig. 2C). Ficus ovaries took on the
typical characters of wasp galls, with shriveled ovary integument enveloping the wasp larva (fig. 5C).
Length 1891.71 ± 8.6 μm, range 1617.15–2178.08 μm; width
1034.29 ± 4.28 μm, range 911.01–1138.11 μm; n = 17. Body
strongly arched and turned white because of the accumulation
of fat bodies. Mid-gut bright yellow, mandibles conspicuously
red. Lateral and latero-ventral protruded, enveloping presumed developing legs and wing bud (fig. 2E). Mandibles well
developed, broader and longer (64.0 ± 0.4 μm in length, n = 12),
and sickle-form in shape, with darker pigmentation on the
bases and margins (fig. 4B, C). Six spiracles presented ventrad
on metasomal segments (VI–XI, fig. 4A). Spiracle VIII larger
than other spiracles, external diameter 97.44 ± 1.2 μm, n = 6
(fig. 4A, B). Mid-gut moved rhythmically. Mobility limited to
the mouthparts. Larva had consumed all the content of each
Ficus ovary, leaving only the outer cast of the gall by the end of
the final instar.
Prepupa (figs 2F and 7)
Fourth-instar larva (figs 2D and 3B, C)
Length 1553.75 ± 8.5 μm, range 1522.39–1938.58 μm;
width 905.35 ± 4.7 μm, range 614.92–1104.67 μm; n = 24. Less
Retained the general morphology of the fifth larval
instar. Abdominal region smoothly arched, a depressed area
presented on the ventral region of abdomen, indicating an
Delimitation and description of the immature stages of a pollinating fig wasp
171
Table 1. The time scale of C. somsi marchali from larva to adult and the significance of differences between sexes using ANOVA.
Stages
Larval instar
Period from hatching to the
first encounter of the instar,
days (mean ± SE)
Female
n
Male
n
F
1
2
4.77 ± 0.03
8 ± 0.03
13
13
4.85 ± 0.03
7.91 ± 0.05
13
11
0.15
0.22
0.70
0.64
3
11.04 ± 0.02
23
10.95 ± 0.03
22
0.39
0.54
4
15.92 ± 0.04
13
15.82 ± 0.07
11
0.17
0.69
5
19.14 ± 0.04
14
19.08 ± 0.04
13
0.11
0.74
Primary
20.13 ± 0.04
21.08 ± 0.04
15
13
20.25 ± 0.04
21.00 ± 0.03
12
14
0.28
0.20
0.60
0.66
Inter-mediate
24.42 ± 0.02
26
23.77 ± 0.02
22
18.99
< 0.0001
Mature
26.65 ± 0.02
28.77 ± 0.01
20
31
25.63 ± 0.02
27.54 ± 0.02
24
26
39.54
117.15
< 0.0001
< 0.0001
Prepupa
Pupa
Adult
Difference between
sexes (ANOVA)
Apparent characters
P
Transparent, inconspicuous segments
Segmentation, active feeding, slender
mandibles
Wide mesosomal segments (II–IV),
broad mandibles
Body curled up, two protrusions on
mesosoma (II–IV), reddish mandibles
Body strongly arched, mandibles
conspicuously red and well developed
Larval form, quiescent
Sexual dimorphism, white for both sexes,
pink eye spots of female
Brilliant red eye spots and ocelli of female,
red mouthparts of male
Female black, male orange
Male emerges earlier, mate behavior
Fig. 7. Prepupa of C. solmsi marchali under SEM: (A) Mandibles of prepupa (21th day post-oviposition), (md: mandible; mp: maxillary palp;
lp: labial palp). (B) Ventral view of metasomal segmentation of pupa under larval skin, showing the depressed area on abdomen (red arrow),
several metasomal segments (XI, XII, XIII), and the last two spiracles (spX and spXI).
initial symptom of pupation (fig. 7B). Mesosomal region
swollened (II–IV), approximate where the wing pads and legs
emerged during pupal stage (fig. 2F). Mandibles resembled
those in the final larval stage (fig. 7A). Pupal cuticle formed,
with rapid internal changes taking place under it. Feeding
completed and wasp was stationary. No peristalsis in the midgut. A period of approximately 1 day was required for this
stage (n = 27).
L.-Y. Jia et al.
172
Fig. 8. Primary pupa of both sexes, showing the compound eyes of female (a), antennae (b), wing buds of female (c), and legs (d): (A, B, C)
Primary pupa of female (21st day post-oviposition) with pink eye spots and longer antennae. Wing buds in C were outspreaded artificially.
(D, E, F) Primary pupa of male (21st day post-oviposition).
Pupal stage
The pupae of C. solmsi marchali were exarate. Adult features
were increasingly evident. The pupal stage could be divided
into three different sub-stages (primary pupa, intermediate
pupa or mature pupa) according to the body color and other
characteristics. At the end of pupal stage, a yellow stain was
found at the bottom of the inner wall of each gall, which was
recognized as a meconium.
In the pupal stage, females could be recognized by the
presence of two pink eye spots and three pink dots on the
female head. They develop into compound eyes (Weiblen,
2002) and three ocelli, respectively, that are absent in males.
The developmental rate of male pupae appeared to be faster
than in females, with males emerging earlier than females
(table 1).
Primary pupa (fig. 8)
Body of both sexes white, divided into head, mesosoma,
and metasoma. Pink compound eyes of females (fig. 8A–C)
became increasingly more intense scarlet. Male pupa slenderer
than female, with no wing buds. The telescopic male metasoma longer and curved. Antennae of the male (fig. 8F) shorter
than the female (fig. 8B). All of these characters reflected the
extreme sexual dimorphism of adult pollinating fig wasp
(Jackson, 1966).
Delimitation and description of the immature stages of a pollinating fig wasp
173
Fig. 9. Intermediate pupa and mature pupa of both sexes, showing the compound eyes of female (a), antennae (b), wing buds of female (c),
legs (d), ocelli of female (e), and mouthparts of male (f): (A, B) Lateral and ventral view of intermediate pupa of female (25th day postoviposition). Wing buds in (B) were outspreaded artificially. (C, D) Intermediate pupa of male (25th day post-oviposition). (E, F) Mature
pupa of female (27th day post-oviposition) with black wing pads. (G, H) Mature pupa of male (27th day post-oviposition).
Approximately 24 days post-oviposition, three ocelli had
emerged on the frons of female pupa, and turned into red, the
same color of the female compound eyes (fig. 9B).
Intermediate pupa (fig. 9A–D)
Female compound eyes and ocelli became brilliant red (on
24.42 ± 0.02 day; n = 26) and intensified gradually, finally
became deep crimson in about 2 days (fig. 9B). Male sclerotized faster than female. Most parts of male’s body turned
yellow except for the reddish mouthparts on 23.77 ± 0.02 day;
n = 22 (fig. 9C, D).
Mature pupa (fig. 9E–H)
Female pupa almost completed transitions, adult characteristics distinct, with black wings compressed in the pupal
cuticle (on 26.65 ± 0.02 day, n = 20). Most parts of female body
turned dark, with red eyes (fig. 9E, F). Males well sclerotized,
turned orange with adult features visible (fig. 9G, H) on day
25.63 ± 0.02 (n = 24). Male pupa in this stage was able to twist
its body slightly, whereas the female would remain stationary.
Males eclosed in an average of 27.54 ± 0.02 (n = 26) days.
Females eclosed in an average of 28.77 ± 0.01 (n = 31) days.
Discussion
Our data show that the entire immature period of C. solmsi
marchali is approximately 28 days (male)–29 days (female)
(table 1). Morphological differences between females and
males before pupation are indistinct, and the duration of egg
and larva development of both sexes was approximately
equal. On average, eggs develop in 5 days; the growth of the
five instars until prepupa lasts another 15 days. Consequently,
the duration of postembryonic development from oviposition
to prepupa is approximately 20 days. However, the time
period since pupation (21st day post-oviposition, both sexes)
to emergence is on average longer in females (8 days) than in
males (7 days). The difference between sexes is significant
since the intermediate-pupal stage. These results are consistent
with the confirmed capacity for protandry in fig wasps
(Joseph, 1984). Protandry means earlier male emergence
(Fagerström & Wiklund, 1982). There are several other documented cases of protandry in Hymenoptera (Bulmer, 1983;
Hastings, 1989).
The morphology of the ovaries of C. solmsi marchali
was similar to that reported in other species of pollinators
(Copland et al., 1973; Ghara & Borges, 2010; Dunn et al., 2011).
The egg load and morphological characteristics of ovarian
eggs of C. solmi marchali concurred with those reported in
Ceratosolen fusciceps, the pollinator of Ficus racemosa (Ghara &
Borges, 2010).
Parker (1924) studied the egg and larval stages of
Chalcidoidea. Although his description of Agaonid larva
was not explicit, larva of C. solmsi marchali fit well into Parker’s
Group II Chalcidoid larvae (Parker, 1924). The other chalcids
in Parker’s Group II include some species of Torymidae,
Eurytomidae, Eulophidae, Pteromalidae, and Elasmidae
(Parker, 1924), phytophages occur in the first four families
(Aeschlimann & Vitou, 1989; Askew, 1998; LaSalle et al., 2005).
Larvae of C. solmsi marchali resemble those of other phytophagous chalcids in the early stages, such as Megastigmus
nigrovariegatus Ashm. (Hymenoptera: Torymidae) (Milliron,
1949) and Eurytoma (Hymenoptera: Eurytomidae) (Williams,
1960). The two lateral and ventro-lateral protrusions emerging in the fourth instar are believed to envelope the
developing legs and wing pads, similar as described in ants
(Brook et al., 1996; Sameshima et al., 2004; Bowsher et al., 2007).
In Holometabola, wing primordium of Apocrita is set aside
from the general larval epidermis before the last larval stage
(Truman & Riddiford, 1999), consistent with our results. The
precise structure of the protrusions needs further investigation.
L.-Y. Jia et al.
174
Our study presents the first detailed description of the
immature stages of the pollinating fig wasp C. solmsi marchali,
which can help us not only in further detailed studies on this
species, but also to compare with the immature stages of other
fig wasps.
Acknowledgements
This project was supported by the National Natural Science
Foundation of China (NSFC grant numbers 31090253,
31172072, and 31210103912), partially by Major Innovation
Program of Chinese Academy of Sciences (grant no. KSCX2EW-Z-2), by Program of Ministry of Science and Technology of
the Republic of China (grant no. 2012FY111100), by a grant
(no. O529YX5105) from the Key Laboratory of the Zoological
Systematics and Evolution of the Chinese Academy of
Sciences, and by the National Science Fund for Fostering
Talents in Basic Research (Special subjects in animal taxonomy, grant no. NSFC-J0930004).
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