Ultrastructure of spermatozoa in Plebeia (Plebeia) droryana Friese (Hymenoptera: Apidae: Meliponina)

10 Pages·2001·5.2 MB·

by  Uyra Zama

HYM. RES.
J.
Vol. 10(2), 2001, pp. 261-270
Ultrastructure of Spermatozoa in Pleheia (Plebeia) droryana Friese
(Hymenoptera: Apidae: Meliponina)
Uyra Zama, Jose Lino-Neto, and Heiui Dolder
(UZ, JL-N, HD) Dept. of Ceil Biology, State University of Campinas (UNICAMP), Campinas,
Sao Paulo, Brazil; (JL-N) Dept. of General Biology, Federal University of Vic^osa (UFV), Vi^osa,
Minas Gerais, Brazil
—
Abstract. In general, the spermatozoa of Plcbcia (Plcbcin) dwri/niui Friese are very similar to
those described forother Hymenoptera. However, theirarrangementinspermatodesmatabundles
in the seminal vesicle has not yet been found in Apidae, this being a characteristic observed, to
date, only in Symphyta, the Hymenoptera considered most primitive. The spermatozoa are long
and thin, made up of a head connected to the tail at the position of the centriolar adjunct. The
head includes an acrosomal vesicle, a perforatorium and a electron dense nucleus. The flagellum
consists in a typical axoneme, two mitochondrial derivatives and two accessory bodies. Unlike
most other Hymenoptera, the centriolaradjunct is very long and locatedbetween thenuclearbase
and the anterior extremity of the smaller mitochondrial derivative. It has recently been demon-
strated that the structure and ultrastructure of hymenopteran spermatozoa are sufficiently varied
so as to furnish consistent character matrices that can contribute to phylogenetic studies ("Sper-
miocladistics")- Since no consensual phylogenetic hypothesis has yet been proposed for Apidae,
the data presented here may be a contribution in this direction.
The Apidae have been extensively stud- such as the Apina and the Meliponina,
ied due to their economic and ecological passing though intermediate social behav-
importance, since they are pc^llinators, of- ior groupings as found in the Bombina
ten exclusively, of the majority of flower- and Euglossina.
ing plants, including species cultivated by In spite of the unc^uestioned importance
man. The relation between these pollinat- of the Apidae, so far neither morphologi-
ing agents and the plants they pollinate is cal nor molecular studies have been able
so intimate that changes in the biodiver- to establish an uncontested phylogeny for
sity of either group is certain to affect the this group (Camargo and Pedro 1992b;
other. The Apidae are also recognized as Cameron 1991, 1993; Cameron et al. 1992).
a diverse group with complex social be- The establishment of the phylogeny ofthis
haviour, which culniinate in advanced eu- group would undoubtedly be important
social societies, a level observed only for studies of the evolutionary mecha-
among Hymenoptera (a few bees anci nism, or mechanisms, leading to eust:>cial
wasps) and in the Isoptera. behaviour (Crozier and Pamilo 1996).
Within the Apidae, the tribe Apini, con- Structural and ultrastructural character-
sisting in the subtribes Apina, Bombina, istics of the spermatozoa, besides their
Euglossina and Meliponina {sciisii Roig- own biological and taxonomic aspects,
Alsina and Michener 1993), is particularly may be very interesting if this information
interesting because its members collective- can be used to form a character matrix for
ly display all levels of social behaviour. phylogenetic analysis. This information,
Ranging from solitary bees, as in some associated with other character systems,
Euglossina, to advanced eusocial groups. could lead to a better understanding ofthe
262 Journalof Hymenoptera Research
ev^olutionary relationships within the (DAPl) in phosphate buffered saline,
group ("spermiocladistics", Jamieson washed, and mounted with Vectashield.
1987) as is being carried out for other an- They were examined with an epifluoresc-
imals, including insects (Baccetti 1972; ence microscope (Olympus, BX60),
Dallai 1979; Dallai and Afzelius 1990, equipped with a BP360-370 nm excitation
1995; Carcupino et al. 1995; Jamieson et al. filter. —
1999; Lino-Neto et al. 1999, 2000a, 2000b). TrniisiJiissioii Electron Microscopy. Sem-
The spermatozoal ultrastructure of only inal vesicles were dissected and fixed for
one apid species. Apis mellifera Limieaus, 3 hours in a solution containing 2.5% glu-
representing the Apini, has so far been taraldehyde, 0.2% picric acid, 3% sucrose
mM M
studied in detail (Rothschild 1955; Hoage and 5 CaCL in 0.1 cacodylate buff-
and Kessel 1968; Cruz-Holfing et al. 1970; er, pH 7.2. The materials were post fixed
Lensky et al. 1979; Woyke 1970; Lino-Neto in 1% osniium tetroxide, in the same buff-
et al. 2000b). Besides this species, in Me- er, for 1-2 hours. Dehydration was carried
liponina only some aspects ofspermiogen- out in acetone and embedded in Epon. Ul-
esis were investigated, including that of trathin sections were stained with uranyl
ScnpUotrigona pwstica Latreille (Cruz-Lan- acetate and lead citrate and observed with
dim and Beig 1980; Cruz-Landim et al. the Zeiss LEO 906 transmission electron
1980), MeUpowi quadrifasciata niifliidioiiics microscc^pe.
Lepeletier (Cruz-Landim et al. 1980; Cruz-
RESULTS
Landim and Moraes 1980), Plcbciii {Plcbcia)
droryaun Friese, FricscomcUtia {FriescouicUi- In the seminal vesicle, the spermatozoa
ta) varia Lepeletier, Lciirotrigoiia mucUcri of Plcbcia {Plcbcia) droryana are organized
Friese (Cruz-Landim et al. 1980). However in spermatodesmata bundles, where the
these publications contain almost no in- anterior region of the heads are embedded
formation on the mature sperm cell. in a substance of medium electron density
Therefore, in this study, we characterize (Figs. 1, 2). The more central spermatozoa
the structure and ultrastructure of Plcbcia are situated slightly ahead of the lateral
{Plcbcia) droryana sperm sc~) as to furnish ones, so that a transverse section of this
data that could be used iov future phylo- region shows acrosomes sectioned at dif-
genetic research. ferent levels (Fig. 2). However, some iso-
MATERIAL AND METHODS lated spermatozoa also appear chaotically
dispersed in the seminal vesicles (Figs. 5-
Adult males of Plcbcia (Plcbcia) droryana 7).
were obtained from colonies maintained The sperniatozoan of P. droryana is long
in the Central Apiary of the Federal Uni- and thin, measuring approximately 135
versity of Vi^osa, MG,—Brazil. |jLm in length (Fig. 3). The acrosome mea-
Light Microscopy. Seminal vesicles suring about 1.2 (jtm and is made up of
were dissected and broken open on clean the acrosomal vesicle and the perforatori-
glass microscope slicies, where the sperm um (Figs. 1, 5-6). The acrosomal vesicle is
were spread and fixed in a solution of 4'/i) cone-shaped and covers the perforatorium
M
(wt/vol) paraformaldehyde in 0.1 phos- along its entire length (Fig. 6). In trans-
phate buffer, pH 7.2. After drying at room verse section, the acrosome is circular at
temperature, the preparations were ob- the tip but beconies triangular, particular-
served with a photomicroscope (Olympus, ly the perforatorium towards the nucleus
BX60), equipped with phase contrast. (Figs. 2, 8-9). Along the circular portion,
To measure the nucleus, some of these an electron transparent layer ct^vers the
preparations were stained for 15 min. with perforatorium, separating it completely
0.2 (xg/ml 4,6-diamino-2-phenylindole from the acrosomal vesicle. However,
VoLUMi: 10, Number 2, 2001 263
when they are triangular this clear layer is smaller in contact with the posterior end
reduced to patches at the vertices (Figs. 8- of the centriolar adjunct. In transverse sec-
9). The perforatorium base penetrates tion, the derivatives are elipsoidal, with
about 70 nm into a small asymmetric cav- the larger one curving slightly over the
ity in the nuclear tip (Fig. 7). smaller one (Fig. 19). Both have at least
The nucleus measures approximately three regions: a dense material that fills in
7.5 |jLm in length and is filled homoge- n"iost of the mitochondrial derivatives; a
neously with dense chromatin. In trans- clear approximately central area and the
verse section, it is slightly oval, measuring region of the cristae, limited to that part
approximately 0.18 |jLm in diameter at the of the periphery opposite the axoneme (a,
anterior extremity and 0.45 jxm at the pos- b and c in Figs. 16-19). The large mito-
terior (Figs. 2-7, 10-13). At the anterior tip chondrial derivative also has a region of
there is a cavity in which the perforatori- regularly arranged paracrystalline mate-
um fits (Fig. 7), while posteriorly the nu- rial in the third that is most distal to the
cleus tapers conically and is covered by axoneme (p in Figs. 16-19). Anteriorly, the
thin electron transparent and electron derivative extremities do not show any
dense material (Figs. 12-13, 15). cristae (Figs. 13-14).
The axoneme, measuring 126 [xm of The accessory bodies are located later-
length, presents the 9+9+2 pattern of mi- ally, between the axoneme and the mito-
crotubules, with 9 single, external, acces- chondrial derivatives. In transverse sec-
sory microtubules, nine doublets and a tions, they have a triangular shape (Figs.
pair of single ones Lri the center of the ar- 18-20). In the cenriolar adjunct region,
rangement (Figs. 18-21). In the first 0.28 there is only one accessory bociy present
fxm, corresponding to the centriole, the ax- between the larger mitochondrial deriva-
oneme consists only of the accessory mi- tive and the axoneme (Fig. 18).
crotubules, the doublets and a dense
DISCUSSION
amorphous substance (Fig. 16). The cen-
tral microtubules begin posterior to the The arrangement of spermatozoa in
centriolar portion (Fig. 17). In the final spermatociesmata observed in Plebcin ciwr-
portion, the axoneme is gradually disor- yana, has not been described for Apocrita.
ganized, with the central microtubules According to Quicke et al. (1992), this
and the nine doublets terminating first, si- spermatozoa arrangement in bundles is
multaneously, followed by the accessory characteristic of Symphyta, considered
microtubules (Figs. 21-24). primitive Hymenoptera, in spite of some
The centriolar adjunct is very long, sheath fragments encountered by these
about 4.6 |jim in length, compact and elec- authors in some Aculeata. The central
tron dense. It begins at the nuclear base spermatozoa of the sheaths are somewhat
and extends parallel to the axoneme until ahead of the others, as observed in P. dror-
it fits onto the smaller mitochondrial de- ynna, as also occurs in Xyeloidea and
rivative (Figs. 11-14). In longitudinal sec- Phamphiloidea, which are considered the
tion, it has a rod-like shape while in trans- most basal Symphyta (Newman and
verse section it is approximately circular, Quicke 1999a). However, in the Siricidae,
with a diameter of about 0.2 ixm (Figs. 1, considered the family most closest to Acu-
11-12, 14, 16-18). leata studied so far, the central spermato-
The mitochondrial derivatives are zoa are inserted well ahead of the periph-
asymmetric in both length and diameter eral ones, so that in transverse sections,
(Figs. 11, 13-14, 19). Anteriorly, the larger they are observed in very different levels
mitochondrial derivative begins next to (Newman and Quicke 1999a). Although
the tapering nucleus (Fig. 13) and the most of the spermatozoa are organized in
264 Journal of Hymenoptera Research
Volume 10, Number 2, 2001 265
spermatodesmata in P. droiynnn, as in the since morphological and molecular anal-
symphytans, Trenicx sp. (Newman and yses suggest that Aculeata are the sister
Quicke 1999a) and Cnlameutn sp. (Quicke group of the Ichneumonoidea (Whitfield
et al. 1992), some spermatozoa are free. and Cameron 1998; Ronquist et al. 1999).
Newman and Quicke (1999a) suggested The basic structure of the spermatozoa
that the observation of free spermatozoa in P. drori/ana is quite similar to that de-
in the seminal vesicle could be due to fix- scribed for other Hymenoptera, as well as
ation or if they indicate a pre-transfer phe- for insects in general (Phillips 1970; Bac-
nomenon. We believe that it is also pos- cetti 1972). The acrosome of P. droryann,
sible that these spermatozoa have either made up of an acrosomal vesicle and the
not yet been grouped into sperniatodes- perforatorium appears to be typical for
mata, or even that not all spermatozoa are Hymenoptera (Jamieson 1999), having
destined to became included in bundles. been found in Symphyta (Quicke et al.
In all the apocritan non-Aculeata (par- 1992; Newman and Quicke 1999a), in the
asitic wasps) considered to date, the sper- Scelionidae, Trissolciis bnsnlis (Lino-Neto
matozoa appear isolated in the seminal and Dolder 2000a), in Formicidae (Wheel-
vesicle, and no spermatodesmata frag- er et al. 1990) and in Apis nicllifera (Cruz-
ments have been observed (ex. Quicke et Hofling et al. 1970; Hoage and Kessel
al. 1992; Newman and Quicke 1998, 1999b; 1968; Lensky et al. 1979; Peng et al. 1992,
Lino-Neto et al. 1999, 2000a; Lino-Neto 1993). In this last species, unlike the other
and Dolder 2001a, b). The fact that sper- Hymenoptera studied, the acrosome is al-
matozoa organized in spermatodesmata most as long as the nucleus, measuring
occur in Symphyta and in at least one apo- about 5.6 |jLm. The fact that the acrosome
critan Aculeata, which are considered, re- of P. droryann shows a circular cross sec-
spectively, the most basal and the most tion at the tip gradually being modified
derived hymenopteran groups, while not into a triangular form as it reaches to-
occurring in the apocritan non-Aculeata, is wards the nucleus differs from other Hy-
very intriguing. This suggests either that menoptera where this acrosome are al-
it could be a reversed character state in ways circular (ex. Symphyta, Newman
Aculeata or that this group derived di- and Quicke 1999a; Cynipoitiea, Newman
rectly from the Symphyta, as is believed and Quicke 1999b; Chalcidoidea, Lino-
to have occurred with parasitic wasps. Neto et al. 1999, 2000a; Lino-Neto and
This latter hypothesis seenis less likely Dolder 2001b; Formicidae, Wheeler 1990),
Figs. 1-14. Ultramicrographs of Plcbeia spermatozoa in seminal vesicle. 1-2, Longitudinal and transverse
sections, respectively, of anterior region of a spermatodesm. 1, Acrosomal region (arrow) and portion of
nucleus (n) embedded in less eletron dense extracellular material (*). The arrowhead indicates thecentriolar
adjunct. 2, Numbers 1-6 indicate acrosomes sectioned in anterior-posterior levels from tip to just above nu-
cleus. 3-4, Phase contrast micrograph of a spermatozoa (3) and head region, DAPI-stained fluorescence of
nucleus. The arrow indicates the head (h) and tail (t) limit. 5, Longitudinal section showing acrosome (ac)
and nucleus. 6, Longitudinal section of acrosomal vesicle (av) and perforatorium (p). 7, Transition region of
acrosome-nucleus showing perforatorium base fitting into cavity of nuclear tip. 8-10, Transverse section of
acrosome tip (8), base of acrosome (9) and nucleus free of extra cellular material (10). 11-13, Longitudinal
sections of nucleus-flagellum transition region. Arrows indicate connective material at nuclear base (12, 13);
14, Longitudinal section at junction of centriolar adjunct and smaller mitochondrial derivative. Arrowhead
indicates mitochondrial cristae. Abbreviations; n = nucleus; ac = acrosome; a\^ = acrossomal vesicle; p =
perforatorium; ca = centriolar adjunct; ax = axoneme; M = larger mitochondrial derivative; m = smaller
mitochondrial derivative. Scale bar: 1, 4, 8-9 = 3|jLm; 2 = 2|jL.m; 3 = 8|xm; 6 = 0,ljjLm; 7 = 0,2(a.m; 10-11, 14
= 0,3|jLm and 5, 12-13 = 0,5|jLm.
266 Journalof Hymenoptera Research
^ ^ >
_ _
20 / 22/ 23
Figs. 15-24. Sequential transverse sections oi tlagella. 15, Nucleus-flagellum transition region. Arrow indi-
cates material connecting nucleus to larger mitochondrial derivative. 16-17, Centriolar region of axoneme.
Open arrow indicates first of central microtubules. 18-19, Sections of flagellum, at centriolar adjunct region
and at both mitochondrial derivatives, respectively. The arrows indicate accessory bodies and (*) indicates
central materialbetween flagellarstructures. 20-24, Final flagellarregion.Theninedoublets(arrowheads)and
two central microtubules (small arrow) terminate first, followed by accessoryones (whitearrowheads).Large
arrows indicateaccessory bodies. Abbreviations: a = lesselectrondenseamorphousregion;b = moreelectron
denseamorphousregion;c = cristaeregion;pc = paracristallineregion in thelargermitochondrialderivative;
ca = centriolaradjunct;ce = centriole; n = nucleus;ax = axoneme. Scalebar: 15-20 = 0,1|xm;21-22 = 0,06|jLm
and 23-24 = 0,05(jLm.
or maintains an oval cross section as in and Quicke 1999a; Wheeler et al. 1990).
Apis mellifcra (q.v.) and Vespidae (personal However, in Eurytomidae, Bcphrntclloidcs
observation). The acrosome of A. niellifern pomoruni Fabricius (Lino-Neto et al. 1999),
also differs from that of P. drorymia due to and in the Pteromalidae, Nasonia vitripen-
the presence of a long anterior projection nis Walker (Hogge and King 1975), the
of the acrosomal vesicle (Cruz-Hofling et perforatorium base is concave and has the
al. 1970; Hoage and Kessel 1968). The pen- same diameter as the nucleus in this re-
etration of the perforatorium in the nucle- gion, fitting directly ontti the anterior nu-
ar tip as occurs in P. droryana has been clear surface, hi the majority of parasitic
described for the majority of the hyme- wasps, there is a third extracellular layer
nc-)pterans (ex. Quicke et al. 1992; Newman (the extracellular sheath), covering all of
Volume 10, Number 2, 2001 267
the acrosome and extending along a vari- Quicke 1999a), Cynipoidea (Newman and
able length of the nucleus (Quicke et al. Quicke 1999b), Ichneumonoidea (Quicke
1992; Newman and Quicke 1999b; Quicke et al. 1998) and in A. mellifera (Lino-Neto
et al. 1992; Newman and Quicke 1998; et al. 2000b). However, in the Ichneumo-
Quicke et al. 1992; Lino-Neto et al. 1999, noidea this structure is comparatively
2000a; Lino-Neto and Dolder 2001b). Also, short (Quicke et al. 1998) while in A. mel-
in some of these, the extra-cellular sheath lifera, it is extremely long, tapered ante-
gives rise to innumerable filaments, prob- riorly, widening into a thick rod posteri-
ably representing a well developed gly- orly (Lino-Neto et al. 2000b). In the sym-
cocalix (Lino-Neto et al. 1999, 2000a; Lino- phytan Treiiiex sp. (Newman and Quicke
Neto and Dolder 2001b). 1999a) and in the Formicidae (Wheeler et
In P. droryana, the nucleus is long, dense al. 1990), the centriolar adjunct lies be-
and usually appears homogeneously com- tween the nucleus and both mitochondri-
pacted. These characteristics are highly al derivatives. On the other hand, in
conserved in Hymenoptera, and the vari- Chalcidoidea (Lino-Neto et al. 1999,
ations observed have been in length and 2000a; Lino-Neto and Dolder 2001b) the
in the fact that this structure may be linear centriolar adjunct is located laterally to
(ex. Quicke et al. 1992; Jamieson et al. the final portion of the nucleus, sur-
1999; Wheeler et al. 1990; Lino-Neto et al. rounding the nuclear-flagellum transition
2000b), or twisted in a spiral, as in Chal- and extending parallel to the axoneme for
cidoidea (Lee and Wilkes 1965; Hogge and a short distance, above the insertion of
King 1975; Quicke et al. 1992; Lino-Neto both mitochondrial derivatives. Contrary
et al. 1999, 2000a, 2000b; Lino-Neto and to the majority of these insects, no cen-
Dolder 2001b), Scelionidae (Lino-Netoand triolar adjunct was encountered in Sce-
Dolder 2001a) and Diapriidae (Quicke, lionidae (Lino-Neto and Dolder 2001a).
personal communicatit^n). The nucleus of The great variation in shape and location
P. droryiDin ends in a short cone, next to of the centriolar adjunct, differing from
the anterior tip of the large mitochondrial that known for most insects (Jamieson
derivative, and terminating in contact 1982) is probably the reason for the ear-
with the centriolar adjunct and axoneme. lier misinterpretations of this element in
In Apis uieUifern, the final nuclear projec- various Hymenoptera (Cruz-Hofling et
tion is considerably longer and inserted in al. 1970; Quicke et al. 1992).
the axoneme, so that in cross section the The mitochondrial derivatives of P.
nucleus is found surrounding the tips of droryana are asymmetric not only in length
the centriolar microtubules (Peng et al. but also in diameter. As a rule, the deriv-
1993; Lino-Neto et al. 2000b). In the ma- atives are straight (ex. Quicke et al. 1992;
jority of the Hymenoptera, the nucleus is Jamieson et al. 1999; Wheeler et al. 1990;
not tapered posteriorly but instead is Lino-Neto et al. 2000b), but in Chalcidoi-
abruptly truncated (Quicke et al. 1992; dea (Lee and Wilkes 1965; Hogge and
Newman and Quicke 1999a; Newman and King 1975; Quicke et al. 1992; Quicke 1997;
Quicke 1999b; Quicke et al. 1992; Wheeler Lino-Neto et al. 1999, 2000a, 2000b; Lino-
et al. 1990; Lino-Neto et al. 1999, 2000a; Neto and Dolder 2001b), Scelionidae
Lino-Neto and Dolder 2001b). (Lino-Neto and Dolder 2001a) and Diapri-
The centriolar adjunct of P. drori/aiin is idae (Quicke, personal communication)
a well developed structure located par- they spiral around the axoneme. The larg-
allel to the axoneme and between the nu- er mitochondrial derivative beginning
cleus and the smaller mitochondrial de- next to the final projection of the nucleus
rivative. This arrangement has also been was also observed in A. ineUifera (Lino-
found in some Symphyta (Newman and Neto et al. 2000b) and in Cynipoidea
268 Journal of Hymenoptera Research
(Newman and Quicke 1999b). This is not Chalcidoidea (Lino-Neto et al. 1999,
the case of the majority of the Hymenop- 2000a).
tera, where the larger mitochondrial de- Plcbcia droryaun, as is common to most
rivative abuts the nuclear base, not over- insects (Jamieson et al. 1999), has an axo-
lapping it (ex. Quicke et al. 1992; Wheeler neme with the microtubules arranged par-
et al. 1990; Jamieson et al. 1999; Newman allel to each other. This is not the case of
and Quicke 1999a). In Megalyroidea Chalcidoidea (Lee and Wilkes 1965; Hog-
(Newman and Quicke 2000), Diapriidae ge and King 1975; Quicke et al. 1992;
(Quicke, personal communication) and Quicke 1997; Lino-Neto et al. 1999, 2000a,
Scelionidae (Lino-Neto and Dolder 2001a) 2000b; Lino-Neto and Dolder 2001b), Sce-
the large mitochondial derivative projects lionidae (Lino-Neto and Dolder 2001a)
parallel to the nucleus for a considerable and Diapriidae (Quicke, personal com-
distance, and in this latter family, only one munication) where they follow a spiraling
large mitochondrion is observed (Lino- course. Also in P. droryaun, the accessory
Neto and Dolder 2001a). In transverse sec- microtubules are the last ones to terminate
tions of the P. don/aiin flagellum, four dis- at the end of the axoneme. This character-
tinct regions make up the larger derivative istic is also observed in A. Dicllifcm (Peng
while only three are found in the smaller et al. 1993; Lino-Neto et al. 2000b) and in
one. The same organization was observed Formicidae (Wheeler et al. 1990), while in
in A. mdlifcra (Lino-Neto et al. 2000b) al- Chalcidoidea (Lino-Neto et al. 1999; Lino-
though Cruz-Hofling et al. (1970), Lensky Neto and Dolder 2000a, b) and Ichneu-
et al. (1979) and Peng et al. (1992, 1993) monoidea (Braconidae) (Newman and
have described the presence of paracrys- Quicke 1998) the accessory tubules termi-
talline material also in the smaller deriv- nate first. Unfortunately, thischaracteristic
ative. In the Formicidae the mitochondrial has not been taken in consideration by
derivatives consist in three regions most studies of hymenopteran spemato-
(Wheeler et al. 1990). However, the re- zoa. We believe this could be a useful pa-
gions described in Formicidae are not rameter to help separate the Aculeata, or
analogous to those in the smaller deriva- parasitic wasps, from other Hymenoptera.
tive of P. dronjiDui. In Formicidae, there is The triangularly shaped accessory bod-
a clear area, a well developed region of ies, as found in transverse sections of P.
cristae and the paracrystalline material sit- droryaun, are encountered in most Hyme-
uated in the mitochondrion's first third, noptera (Quicke et al. 1992; Jamieson et al.
proximal to the axoneme (Wheeler et al. 1999; Wheeler et al. 1990; Lino-Neto et al.
1990). Asymmetrical diameters of mito- 2000b). They may be considerably reduced
chondrial derivatives are frequently in Chalcidoidea (Lino-Neto et al. 1999,
found, occurring in the Symphyta (Quicke 2000a; Lino-Neto and Dolder 2001b) and
et al. 1992; Newman and Quicke 1999a), in the Scelionidae (Lino-Neto and Dolder
Cynipoidea (Quicke et al. 1992; Newman 2001a) so that, in some cases, they are dif-
and Quicke 1999b), Megalyroidea (New- ficult to identify. The function of this
man and Quicke 2000) and Proctotrupo- structure has not been clearly established
idea (Quicke et al. 1992). However, bees but they appear to be involved in the at-
are even more strongly asymmetrical tachment of the mitochondrial derivatives
(Cruz-Hofling et al. 1970; Hoage and Kes- on to the axoneme, since they do not occur
sel 1968; Lensky et al. 1979; Peng et al. between the centriolar adjunct and the ax-
1992, 1993; Lino-Neto et al. 2000b). On the oneme.
other hand, some Hymenoptera have In P. droryaun a small central structure
symmetrical mitochondrial derivatives as was identified between both the mito-
in Formicidae (Wheeler et al. 1990) and chondrial derivatives and the axoneme
Volume 10, Number 2, 2001 269
(see asterisk in Figs. 18 and 19). This struc- emy Science of lliuted States ofAmerica 90: 8687-
ture was initially described in Formicidae 8691.
(Wheeler et al. 1990), but it is possible that Cameron,S. A.,J. N. Derr,A. D. Austin,J. B. Woolley
it is present in the majority of Hymenop- calnedotRi.deAs.sWehqauretnocne.da1t9a92.toTphheylaoppgleincyatoifonthoefHnyu--
tera (Lino-Neto et al. 2000b). menoptera: A review, journal ofHymenoptera Re-
Based on the characteristics compared searcli 1: 63-79
above, the sperniatozoa of this bee are, for Carcupino, M., G. Profili, J. Kathirithamby, and M.
the most part, similar to the majority of Mazzini. 1995. Sperm ultrastructureofXenosves-
the Hymenoptera (Jamieson et al. 1999). pmayruamnd(Rposhsyil)oagnendyitosfsSitgrneipfsiicpatnecreain(Intsheecttaa).xoMneo--
Some distinct differences stand out. For moires du Museum National d'Histoire Naturelle
example: (1) the arrangement of sperma- 166: 291-296.
tozoa in spermatodesmata in the seminal Crosier, R. H. and P. Pamilo. 1996. Evolution ofInsect
vesicle, (2) the presence ofa very long cen- Cokviies: SexAllocation and King Selection. Oxford
triolar adjunct between the nucleus and University Press: 1-28.
the smaller mitochondrial derivative and Cruz-Hofling, M. A., C. Cruz-Landim and E. W. Ki-
tajima. 1970. The fine structure of spermatozoa
(3) the presence of abundant paracrystal- from the honey bee. Anais da Academia Brasileira
line material, exclusively in the large mi- de Ciencia 42: 69-78.
tochondrial derivative. Cruz-Landim, C. and D. Beig. 1980. An electron mi-
The identification of these characteris- croscopic study of spermatogenesis in the drone
tics and other more subtle ones suggest of Scaptotrigona postica (Hymenoptera: Apidae).
that the sperm cell can furnish a character Intenational journal ofInvertebrate Reproduction 2:
271-283.
matrix for Hymenoptera that will be use- Cruz-Landim, C. and R. L. M. Silva de Moraes. 1980.
ful for future phylogenetic studies. Observations on the mitochondrial complex and
head differentiation during spermiogenesis of
ACKNOWLEDGMENTS
the stingless bee Melipona quadrifaciata anthidioi-
des Lep. Cytobios 27: 167-175.
The authors would like to thank Professor Dr. Lu- Cruz-Landim, C, D. Beig and R. L. M. Silva de Mo-
cioAntoniodeOliveiraCampos(DBG/UFV)forsup- raes. 1980. Processofdifferentiationduringsper-
plying the insects. This research was supported by matogenesis in bees (Hymenoptera, Apidae).
the Brazilian Agencies CNPq and FAPESP. Caryologia 33 (1): 1-15.
Dallai, R. 1979. An overview ofatypicalspermatozoa
LITERATURE CITED in insects. In: The Spermatozoon, (eds.). W. Faw-
cett and J.M. Bedford: 253-256. Urban and
Baccetti, B. 1972. Insect Sperm Cell. Advanced bisect Schwarzenberg, Baltimore.
Phifsiology 9: 315-397. Dallai, R. and B. A. Afzelius. 1990. Microtubular di-
Camargo,J. M. F. and S. R. M. Pedro. 1992a. System- versity in insect spermatozoa: results obtained
atics, phylogeny and biogeography of the Meli- with a new fixative. Journal ofStructural Biology
poninae (Hymenoptera, Apidae) a mini review.
103: 164-179.
Apidohgic 23: 1-32. Dallai, R. and B. A. Afzelius. 1995. Phylogeny signif-
Camargo, J. M. F. and S. R. M. Pedro. 1992b. Siste- icance of axonemal ultrastructrure: examples
matica de Meliponinae (Hymenoptera: Apidae): from Diptera and Trichoptera. Mcmoires du Mu-
sobre a polaridade e sigiiificado de alguns car-
seum Nationald'Histoire Naturelle 166: 301-310.
Cachtaeurdes-Nmeotrof,olAoigmiicsosd.oInE:ncCo.iiCtrwuBzr-aLsailnediiwmdeanBdiolJ-. Hoage, T. R. and R. G. Kessel. 1968. An electron mi-
ogiadeAbelhaseoutivs hisetos Sociais. Ed. UNESP. croscope study of the process of differentiation
Sao Paulo. Pp. 45-49 during spermatogenesis in the drone honey bee
Cameron, S. A. 1991. A new tribal phylogeny of the {Apis mellifera L.) with special reference to cen-
Apidae inferred from mitochondrial DNA se- triole replication and elimination, journal of LIT
quences. In: D. R. Smith (ed.). Diversity in thege- trastructureResearch 24: 6-32.
nus Apis. Westview Press, Bonder,Colorado,pp. Hogge, M. A. F. and P. E. King. 1975. The ultrastruc-
71-78 ture of spermatogenesis in Nasomia vitripennis
Cameron, S. A. 1993. Multiple origins of advanced (Walker) (Hymenoptera: Pteromalidae). Journal
eusociality in bees inferred from mitochondrial Submicroscopic Cytology 7: 81-96.
DNA sequences. Proceedings ofthe NationalAcad- lamieson, B. G. M. 1987. The Ultrastructure and Phy-
270 Journal of Hymenoptera Research
logciiy ofInsect Spermatozoa. Cambridge Univer- menoptera: Symphyta). Journal of Hymenoptera
sity Press, Cambridge, 320 pp. Research, 8: 35^7.
Jamieson, B. G. M., R. Dallaiand B. A. Afzelius. 1999. Newman, T. M. and D. L. J. Quicke. 1999b. Ultra-
bisects:TheirSpermatozoaandPliylogeni/. Scientific structureofspermatozoa inLeptopilia(Hymenop-
Publisiiers, Enfield, New Hampshire, USA, 555 tera: Cynipoidea: Eucoilidae). journal of Hyme-
PP- noptera Research 8: 197-203.
Lee, P. E. and A. Wilkes. 1965. Polymorphic sper- Peng, C. Y. S.,C. M. Yin and L. R. S. Yin. 1992. Effect
matozoa in the hymenopterous wasp Dahlbonu- of rapid freezing and thawing on cellular integ-
luts. Science 147: 1445-1446 rity ofhoney beesperm. Physiological Entomology
Lensky, Y., E. Ben-David and H. Schindler. 1979. Ul- 17:269-276.
trastructure of the spermatozoan of the mature Peng, C. Y. S., C. M. Yin and L. R. S. Yin. 1993. Ul-
dronehoneybee.JonriialofApicultureResenrcli18: trastructure of honey bee. Apis mellifera sperm
264-271. withspecialemphasison theacrosomalcomplex
Lino-Neto,J.,S. N. BaoandH.Dolder. 1999.Structure following high-pressure freezing fixation. Physi-
and ultrastructure of the spermatozoa of Bephra- ological Entomology 18: 93-101.
telloides pomorum (Fabricius) (Hymenoptera: Eur- Phillips, D. M. 1970. Insectsperm: structureand mor-
ytomidae). International lournal ofInsect Morphol- phogenesis. Journal ofCell Biology 44: 243-277.
ogy aiui Embryologi/28: 253-259. Quicke, D. L. J. 1997. Parasitic Wasps. Chapman and
Lino-tNueretoa,nd].,uSl.trNa.stBraucotuarnedofH.theDoslpdeerrm.a2t0o0z0oaa.oSftrTurci-- QuickHeal,l,D.LoL.ndJ.o,nS,.4N7.0Ipnpg.ram, H. S. Baillie and P. V.
Gaitens. 1992.Spermstructureandultrastructure
cliogrammapretiosum Riley and Tricliograunna ato-
povirilia Oatman and Platner (Hymenoptera: Tri- in the Hymenoptera (Insecta). Zoologica Scripta
21:381-402.
chogrammatidae). Acta Zoologica (Stockholm) 81:
Roig-Alsina, A. and C. D. Michener. 1993. Studies of
205-211.
Lino-uNletrtaos,trJ.u,cSt.urNe.oBfatoheahnodneH.yDboeled{eArp.is20m0e0llbi.feSrap)e(rLm) bteheesph(yHlyomgeennoyptaenrda:claAspsoiifdiceaat)i.onTohfelUonnigv-ertsointgi/ueodf
Kansas Sciowe Bulletin, 55: 123-162.
(Hymenoptera, Apidae) with emphasis on the
Ronquist, F., A. P. Rasnitsyn, A. Roy,K. Erikssonand
nucleus-flagellum transition region. Tissue and M. Lindgren. 1999. Phylogeny of the Hymenop-
Cell, 32: 322-327. tera: A cladistic reanalysis of Rasnitsyn's (1988)
Lino-Neto, and H. Dolder. 2001a. Ultrastructural
J. data. Zoologica Scripta 28: 13-50.
characteristics ofthe spermatozoa ofScelionidae Rothschild, L. 1955. The spermatozoa of the honey
(Hymenoptera; Platygastroidea) with phyloge-
bee. Transactions ofthe RoyalEntomologicalSociety
netic considerations. Zoologica Scripta 30 (2): 89- ofloihlon. 107: 289-294.
96. Woyke, 1984. Ultrastructure ofsingle and multiple
Lino-Neto, ]. and H. Dolder. 2001b. Redescription of diplJo.id honey bee spermatozoa. Journal of Hy-
spermstructureand ultrastructureofTr/c7;o^^^r(7/»- menoptera Research 23: 123-135.
tua dendrolimi (Hymenoptera: Chalcidoidea: Tri- Wheeler, D. E., E. D. Crichton and P. H. Krutzsch.
chogrammatidae). Acta Zoologica 82 (2): 159-164. 1990. Comparative ultrastructure of ant sperma-
Newman, T. M. and D. L. J. Quicke. 1998. Sperm de- tozoa (Formicidae: Hymenoptera).jouriuilofMor-
velopment in the imaginal testes ofAleiodes cox- phology 206: 343-350.'
alis (Hymenoptera: Braconidae: Rogadinae).jour- Whitfield,]. B., S. A. Cameron. 1998. Hierarchical
nal ofHymetioptern Researcli 7: 25-37. analysis of variation in the mitochondrial 16S
Newman,T. M.and D. L. |.Quicke. 1999^1. Ultrastruc- rRNA gene among Hymenoptera. Molecular Bi-
ture of imaginal spermatozoa of sawtlies (Hy- ology and Evolution 15: 1728-1743.