Immatures of Rophitine Bees, with Notes on their Nesting Biology

36 Pages·2008·17.16 MB·Turkish

PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY
CENTRAL PARK WEST AT 79TH STREET, NEW YORK, NY 10024
Number 3609, 36 pp., 74 figures April 9, 2008
Immatures of Rophitine Bees, with Notes on their
Nesting Biology (Hymenoptera: Apoidea: Halictidae)
JEROME G. ROZEN, JR.,1 AND HIKME T. O¨ZBEK2
ABSTRACT
This study is a taxonomic overview of the known mature larvae and pupae of the Rophitinae
(Halictidae).Weeitherdescribeandillustratethematureornearlymaturelarvaeofthefollowing
taxa or provide references to their earlier descriptions: Dufourea holocyanea (Cockerell), D.
australis australis Michener, D. mulleri (Cockerell), D. novaeangliae (Robertson), Sphecodosoma
(Sphecodosoma) dicksoni (Timberlake), Protodufourea eickworti Bohart and Griswold, Xeralictus
timberlakei Cockerell, Systropha planidens Giraud, Rophites (Rhophitoides) canus Eversmann, R.
(Rophites)algirus trispinosus Pe´rez,Conanthalictus (C.)conanthi (Cockerell), and C.(Phaceliapis)
bakeriCrawford.Wepresentakeytoknownmaturerophitinelarvae.Wealsodescribepupaeof
thefollowingtaxaforthefirsttimeandcomparethemwiththepupaofS.dicksoni:D.holocyanea,
D.australisaustralis,andR.canus.Thephylogeneticrelationsofthetreatedtaxaarediscussedin
lightof larvalcharacters, and wediscuss the pupal characteristicsof the entire family.
We offer notes on the nesting biology of various taxa whose immatures were treated and
synthesizethisinformation withpreviousaccounts from the literature.
ABSTRAKT
Buc¸alıs¸ma,Rophitinae(Halictidae)’ninbilinenolgunlarvavepupalarınıntaksonomikyo¨nden
go¨zden gec¸irilmesine yo¨neliktir. Bu alt familyada yer alan Dufourea holocyanea (Cockerell), D.
australis australis Michener, D. mulleri (Cockerell), D. novaeangliae (Robertson), Sphecodosoma
(Sphecodosoma) dicksoni (Timberlake), Protodufourea eickworti Bohart and Griswold, Xeralictus
timberlakei Cockerell, Systropha planidens Giraud, Rophites (Rhophitoides) canus Eversmann, R.
1DivisionofInvertebrateZoology,AmericanMuseumofNaturalHistory ([email protected]).
2Atatu¨rk University, Faculty of Agriculture, Department of Plant Protection, 25240 Erzurum, Turkey (hozbek@
atauni.edu.tr).
CopyrightEAmericanMuseumofNaturalHistory2008 ISSN0003-0082
2 AMERICAN MUSEUMNOVITATES NO. 3609
(Rophites) algirus trispinosus Perez, Conanthalicus (C.) conanthi (Cockerell), ve C. (Phaceliapis)
bakeri Crawford tu¨rlerinin olgun veya olgun olmak u¨zere olan do¨nemlerdeki larvaları, ya
tanımlanmıs¸vec¸izimleriyapılmıs¸veyadahaonceyapılantanımlaraatıflaryapılmıs¸tır.Bilinentu¨m
rophitineolgunlarvalarıic¸intanıanahtarıhazırlanmıs¸,D.holocyanea,D.australisaustralis,veR.
canus tu¨rlerinin pupaları ilk defa tanımlanmıs¸ ve bunlar, daha o¨nce tanımı yapılmıs¸ olan S.
dicksoni tu¨ru¨nu¨npupasıile kars¸ılas¸tırlmıs¸tır.
Ele alınan tu¨rlerin larva o¨zelliklerinin ıs¸ıg˘ı altında, filogenetik ilis¸kiler tartıs¸ılmıs¸ ve tu¨m
familyanın pupa o¨zellikleri deg˘erlendirilmis¸tir.
Genc¸do¨nemleric¸alıs¸ılandeg˘is¸iktu¨rlerdeyuvaileilgilibiyolojiknotlarverilmis¸,bubilgilerdaha
o¨nce bilinenlerle literaru¨re dayalı olarak kars¸ılas¸tırılmıs¸ ve ayrı bir bo¨lu¨m halinde makalenin
sonundaverilmis¸tir.
INTRODUCTION one taxon with another due to its thick, rigid
integumentascomparedtothatofpredefecat-
TheimmaturestagesoftheRophitinaewere
ing forms. In the current study we used
studied as a group well over a decade ago
various earlier stages of the last instar when
(Rozen,1993),andthedescriptionofthelarva
postdefecating representatives were not avail-
of Xeralictus was published several years later
able. Because head characteristics (except for
(Snelling and Stage, 1995). Since then mature
degree of pigmentation) do not change within
larvae (i.e., both predefecating and postdefe-
aninstar,evenayounglastinstaroffersmany
cating larvae) of a number of additional taxa
features of comparative value.
have become available. These are described
Althoughwedescribethepaireddorsalbody
here to provide a more complete understand-
tubercles of rophitine mature larvae as ‘‘coni-
ing of the range of anatomical variation
cal’’, each is often wider than its longitudinal
among mature larvae in the subfamily.
length. However, they contrast with paired
Because the pupa of only Sphecodosoma
dorsalbodytuberclesofhalictines,whichareso
(Sphecodosoma) dicksoni (Timberlake) has
transversethatthoseonthesamebodysegment
been described to date (Rozen, 1993), we
nearly meet dorsally at the midline and extend
include comparative descriptions of pupae of
laterallyontothesidesofthesegment.
additional taxa to begin exploring anatomical
In studying the specimen, we first examined
variation in that life stage. In the process of
and illustrated untreated specimens, either
excavating nests, we recorded information
while they were alive or after they were
about the nesting biology of some of the
preservedinKahle’ssolution.Illustrationswere
species; this information is presented in the
prepared with a camera lucida attached to a
Remarks sections of the larval descriptions of
stereomicroscope. Specimens were then decap-
each of these species. It is synthesized with
itated, and the head and body were cleared in
previous accounts from the literature in
‘‘Discussion of Rophitine Nesting Biology’’. an aqueous solution of sodium hydroxide,
washed in water, transferred to ethanol, and
then stained with Chlorazol Black E. After
Terminology and Methods
preparation, the cleared specimens were exam-
Species determinations of immatures are ined in glycerin on well slides, and such
based on associated adults. informationasinternalheadridges,spiculation,
The term mature larva refers to the last and sensilla were added to the illustrations.
larval instar after it completes defecation Mandibles and spiracles were illustrated from
(postdefecatinglarva)orjustafteritconsumes cleared specimens. When possible, we studied
all or nearly all larval provisions but has not both predefecating and postdefecating (prepu-
yetstartedtodefecate(predefecatinglarva).In pal) larvae. Because of their thick cuticle, the
studies of bee larvae, the postdefecating form bodiesofthelattertendtoretaintheiroriginal
is usually described because this form is most shape after preparation, whereas the postce-
commonlyencountered(univoltinebeesspend phalic integument of the predefecating larva
about 10 months per year in this stage) and losesitsshapeandoftentears.
because it is the form that can be most easily Larvae were examined with a Hitachi S-
recognized and most reliablyused to compare 5700 scanning electron microscope (SEM) in
2008 ROZEN AND O¨ZBEK: IMMATURESOFROPHITINE BEES 3
the Microscopy and Imaging Facility of the additional larval features support this place-
AMNH after they had been critical-point ment. The paired truncate dorsal body tuber-
dried and coated with gold/palladium. cles, a unique synapomorphy among bees, are
Postdefecating larvae that had not been evidentinXeralictus,Protodufourea,Rophites,
cleared in an aqueous solution of sodium and many Dufourea, although the degree of
hydroxide were inadequate for such examina- expression is variable. The close relationship
tion because many features were obscured by between Xeralictus and Protodufourea is fur-
the flaking remnants of the dried coating that thersupportedbythelong,curveddeclivityon
covers postdefecating larvae (see description the dorsal and ventral mandibular surfaces.
under ‘‘Remarks’’ in treatment of Dufourea a. Do larval features inform us about the
australis, below). interrelationships within the Rophitinae?
As demonstrated in a recent study of other Several recent investigations using adult mor-
bee larvae (Rozen and Kamel, 2007), the phologicalandmoleculardata(Danforthetal.,
interesting variation in the internal structure 2004, 2006) provide a number of cladograms
of the salivary opening of cocoon-spinning showing somewhat variable topologies, due in
rophitinebeesapparentlyisrevealedonlyafter part to different generic representation. In
the specimen has been subjected to critical- common to both studies were Conanthalictus,
point drying. Penapis, Xeralictus, Dufourea, and Systropha,
Pupae required no special treatment; they but one study included Rophites and theother
were drawn while in alcohol. In their descrip- examined Goeletapis, Protodufourea, and
tions, T 5 tergum and S 5 sternum, followed Sphecodosoma. Larval data do not include
by Arabic numerals signifying the metasomal eitherPenapisorGoeletapis.Thus,substantive
segment, e.g., S6 5 sixth metasomal sternum. analyses based on all lines of evidence must
AMNH 5 American Museum of Natural await further studies incorporating adult and
History. molecular data and the discovery of the
immatures of additional taxa, particularly of
theSouthAmericanRophitinae.
DISCUSSION OF RELATIONSHIPS
Withpupaeofonlyfourrophitinetaxanow
To what extent do larval features reveal studied, too few are known to shed light on
information about the monophyly of the the interrelationships of these taxa. Their
subfamily Rophitinae? Although immatures pupae are similar, and, as discussed in the
of the South American genera as well as of section ‘‘Pupal Characters of the Halictidae’’,
Morawitzella and Morawitzia have yet to be below, pupal characters within the family are
discovered, larvae of the other genera suggest sufficiently variable to suggest that they may
that the subfamily is monophyletic: On most eventually be useful in determining relation-
species,paireddorsalprothoracictuberclesare ships within the family.
smaller than the paired tubercles on the other
thoracic segments (a feature that is best MATURE LARVAE OF
evaluated on postdefecating larvae) as well as THE ROPHITINAE
on most abdominal segments. The only
exception is Conanthalictus, in which the Rozen (1993) presented a diagnostic de-
prothoracic tubercles are absent. However, scription of the subfamily Rophitinae based
that condition is likely a character-state upon larval characters. That characterization
transformation from the reduced prothoracic suffices now; it is unaltered by information
tubercles of other rophitines, since no other from the current study, except for one feature
bee larva in any family is known to have that was not appreciated at that time: the
paired dorsal tubercles only on the meso- and anterior tentorial pits of rophitine larvae lie
metathorax. Xeralictus, once placed in the close to the anterior mandibular articulation.
Halictinae (Michener, 1944), was recently As a consequence they are immediately above
recognized as a rophitine on both larval and the articulations or above and slightly laterad
adult morphological features (Snelling and ofthem.InotherHalictidaethepitsareabove
Stage, 1995). The current study shows that and much farther mesad of the articulations
4 AMERICAN MUSEUMNOVITATES NO. 3609
(Rozen, 2008). The following key treats all – Antennaldiscvariableindiameterbutpapilla
taxa whose mature larvae are known; it is smaller,apicallymorepointed,withsensil-
expanded and modified from a previous one la tightly clustered as seen on cleared
specimen with compound microscope3, so
(Rozen, 1993). To be seen, many characters
that no sensillum farther removed from
must be observed on cleared specimens.
others by more than one diameter
(Dufourea); subatrium shorter, usually
composedof 15orfewerchambers. .. . 5
KEYTO MATURE LARVAE 5(4). Salivarylipsverynarrow,sothatapicalwidth
oflipsaboutsameasdistancefromlipsto
1. Prothoracic paired dorsal tubercles present labial palpus in frontal view (figs. 10,
but smaller than those of following seg- 18) . . .. .. .. Dufourea australis australis
ments(figs.1,2,23,31,50);labiomaxillary Michener
regionnotrecessed(figs. 4,33,53);labium – Salivary lips normally broad, so that apical
divided into prementum and postmentum; width of lips much greater than distance
projecting transverse salivary lips present from lips to labial palpus in frontal view
(figs. 4, 13, 19, 23, 42, 57); maxillary and (figs. 3, 12, 28; McGinley, 1987: fig. 27,
labialpalpiaslongasorlongerthanbasal 187a). .. .. .. .. .. .. . .. .. .. .. .. . 6
diameters.. .. . .. .. .. .. .. .. .. . .. 3 6(5). Antennaldiscsmall,itsdiameteralmostone-
– Prothoracic paired dorsal tubercles absent, half distance from its lower margin to
although paired dorsal tubercles of meso-, center of anterior tentorial pit (fig.28);
metathoracic, and many abdominal seg- antennal papilla projecting more strongly,
ments present (figs. 64, 65); labiomaxillary length more than one-half basal diameter
region greatly recessed (fig. 67; Rozen, as seen in maximum lateral profile
1993: fig. 35); labium undivided (Rozen, (fig. 30). .. Dufourea mulleri (Cockerell)4
1993: fig. 35) or weakly divided into – Antennal disc moderately large, its diameter
prementum and postmentum (figs. 67); only slightly less than distance from its
salivary opening without projecting lips lowermargintocenterofanteriortentorial
(fig. 67); maxillary palpi (figs. 66, 67) pit (fig. 3); antennal papilla projecting
scarcely evident; labial palpi undeveloped weakly, length at most one-half basal
except forsensilla. Conanthalictus.. . .. 2 diameter as seen in maximum lateral
2(1). Paired dorsal body tubercles projecting less, profile (fig. 6). .. .. Dufoureaholocyanea
apically rounded(figs. 64, 65) .. .. . .. . (Cockerell)
. .. .. ..C.(Phaceliapis)bakeri Crawford 7(3). Labral tubercles forward directed, projecting
(or deserticolaTimberlake) beyond clypeus in lateral view (fig. 53;
– Paireddorsalbodytuberclesprojectingmore, Rozen,1993: fig.42) (Rophites). .. .. . 8
apically more pointed (Rozen, 1993: fig. – Labral tubercles at best low mounds, not
37) .. .. .. . C.(Conanthalictus)conanthi projecting beyond clypeus in lateral view
(Cockerell) (asin fig.33) . .. .. .. . .. .. .. .. .. . 9
3(1). Articulatingarmofstipes(asseenoncleared 8(7). Salivary lips extremely narrow, their apical
headcapsule)notevidentorrarelyappear- width much narrower than distance be-
ing as slight anterior projection on distal tween their lateral edge and base of
endofstipes;labiumtendingtoprojectwell maxillary palpus in frontal view (Rozen,
beyond maxillary apices in lateral view 1993:fig.41);antennalpapillainmaximum
(fig. 4) (Dufourea andSphecodosoma).. 4 profile acutely rounded, as long as basal
– Articulatingarmofstipes(asseenoncleared
head capsule) present; labium tending to
project little beyond maxillary apices in
lateral view(figs. 33,53)... .. .. .. . .. 7 3Antennalsensillaappearmuchlargerwhenviewedwith
4(3). Antennal disc and papilla large; papilla a compound microscope than with an SEM. With a
apically rounded, with at least one sensil- compound microscope, the sensillum is identified by its
lum removed from others by several muchlargeralveolus(fig.3)whereasthesensillumitselfis
mostapparentwithanSEMwhereitsalveolusisscarcely
diameters as seen on a cleared specimen
discernable(figs.16,43,59).
with a compound microscope3; subatrium 4FromtheillustrationprovidedbyEickwortetal.(1986:
abnormally long, of considerably more
fig. 12), Dufourea novaeangliae (Robertson) would also
than15chambers. .. .. . Sphecodosoma key out here because of the strongly projecting antennal
(Sphecodosoma)dicksoni (Timberlake) papilla.
2008 ROZEN AND O¨ZBEK: IMMATURESOFROPHITINE BEES 5
Figs. 1–9. Dufourea holocyanea. 1. Entire postdefecating larva, lateral view. 2. Predefecating larva,
lateralview.3.Head,frontalview.4.Head,lateralview.5.Spiracle,sideview.6.Antenna,maximumlateral
profile.7–9. Rightmandible, dorsal, inner, andventral views, respectively. Scalerefers to figs. 1,2.
diameter . . .. Rophites (Rophites)algirus 9(7). Mandiblewithoutdeclivityonventralsurface
trispinosus Pe´rez traversingfromoutertubercleclusterto,or
– Salivarylipswider,theirapicalwidthequalto nearly to, base of cusp (fig. 41) (declivity
distancebetweentheirlateraledgeandbase easily confused with wrinkles in similar
ofmaxillarypalpusinfrontalview(fig. 52); position on dorsal surface of cleared
antennal papilla in maximum profile specimen). Old World. .. .. .. .. .. .. .
broadly rounded, much shorter than basal . . .. .. .. .. Systrophaplanidens Giraud
diameter . . Rophites(Rhophitoides) canus – Mandible with declivity on ventral surface
Eversmann traversing as a line from outer tubercle
6 AMERICAN MUSEUMNOVITATES NO. 3609
cluster to, or nearly to, base of cusp
(fig. 35).North America... .. .. .. . . 10
10(9).Internal epistomal ridge mesad of anterior
tentorialpitpigmented,fadingouthalfway
between pit and head midline; pigmented
internalsecondaryridgeextendingpartway
toward antenna from anterior tentorial
pit. .. .. Xeralictus timberlakei Cockerell
– Internal epistomal ridge mesad of anterior
tentorialpitunpigmented,virtuallyabsent;
pigmentedinternalsecondaryridgeextend- Figs. 10, 11. Dufourea a. australis, postdefecat-
ing from anterior tentorial pit toward inglarva.10.Frontalviewoflabiomaxillaryregion
antenna notevident . .. .. Protodufourea showing narrow salivary opening. 11. Antenna,
eickworti BohartandGriswold maximumlateralprofile.
not obviously setiform; those of mouthparts
Mature Larvae of Dufourea
with small setae; spiculation as described
DIAGNOSIS: MaturelarvaeofDufoureacan below. Integument unpigmented except for
immediately be distinguished from those of mandibular apices and anterior and posterior
Conanthalictus because the latter have a mandibular articulations.
recessed labiomaxillary region, the salivary Head (figs. 1, 2) moderately small com-
opening lacks projecting lips, and the protho- paredwithbodysize;headcapsulewiderthan
racic dorsal tubercles are absent. The labio- length measured from top of vertex to lower
maxillary region of Dufourea is forward clypeal margin in frontal view. Tentorium
projecting with pronounced salivary lips, and complete, including dorsal arms. Anterior
the prothorax bears a distinct pair of dorsal tentorial pit close to anterior mandibular
tubercles. Unlike all other known rophitines articulation (fig. 3); posterior tentorial pits in
except for Sphecodosoma, mature larvae of normal position; postoccipital ridge moder-
ately developed, becoming weaker toward
Dufourea lack a well-defined articulating arm
vertex;medianlongitudinalthickeningofhead
of the stipes. The large, rounded antennal
capsule nearly absent; hypostomal ridge mod-
papilla of Sphecodosoma separates that genus
erately developed, its posterior section divid-
from Dufourea, all known mature larvae of
ingintodorsallycurvingramusthatfuseswith
whichhavesmallerantennalpapillae,withthe
postoccipital ridge while ventral ramus bend-
sensilla tightly clustered at the apex of the
ing mesad to join postoccipital ridge at
papilla. The characters presented in the key
posterior tentorial pit (best seen in postero-
should distinguish the species of Dufourea
ventral view of cleared head capsule); pleur-
whose larvae were available for this study.
ostomal ridge well developed; epistomal ridge
These larvae,however,areverysimilar oneto
laterad of anterior tentorial pit short because
another.
of closeness of pit to anterior mandibular
articulation; ridge between pits fading out
Mature Larvae of Dufourea holocyanea before reaching midline. Parietal bands evi-
(Cockerell) dent as integumental scars. Antennal promi-
Figures 1–9, 12–17 nence rather weak; antennal disc moderately
large, its diameter only slightly less than
DIAGNOSIS: The combination of normally distance from its lower margin to center of
broad salivary lips (fig. 3) and moderately anteriortentorialpit(latterdistancemeasured
large antennal disc (fig. 3) distinguish the in maximum profile); papilla projecting mod-
mature larva of Dufourea holocyanea from erately,itsheightnomorethanone-halfbasal
thoseofD.mulleri,whichhasasmallantennal diameter, each bearing 3 sensilla (figs. 6, 16).
disc (fig. 28), and D. australis australis, which Vertex evenly rounded, moderately broad, as
has narrow salivary lips (fig. 10). seen from side, without projections. Labrum
HEAD (figs. 3, 4): Integument of head not projecting anteriorly as far as clypeus in
capsule with scattered small sensilla that are lateral view (fig. 4), moderately short in
2008 ROZEN AND O¨ZBEK: IMMATURESOFROPHITINE BEES 7
Figs. 12–17. SEM micrographs of predefecating larva of Dufourea holocyanea. 12. Head, frontal view.
13.Labiomaxillaryregion.14.Apexoflabium.15.Close-upofsalivaryopening.16.Antenna,showingthree
sensilla. 17. Spiracle.
frontal view (figs. 3, 12), apically shallowly sharp teeth; ventral apical edge with evenly
bilobed when viewed anterodorsally; labrum spaced, sharp teeth; cusp moderately pro-
spiculate laterally. duced in dorsal and ventral views (figs. 7, 9),
Mandible in adoral view tapering to nar- with numerous teeth; apical concavity shal-
rowly pointed apex; dorsal apical edge with low, facing hypopharyngeal surface; outer
8 AMERICAN MUSEUMNOVITATES NO. 3609
mandibular surface with cluster of three or
four conspicuously projecting tubercles, each
bearing single short sensillum; apical dorsal
surface with series of parallel ridges (some
apparently with fine denticles) running in
same direction as cuspal teeth; ventral surface
with transverse declivity extending from outer
tuberclestowardcups,butthisdeclivitynotas
pronounced or long as that of Xeralictus
timberlakei and apparently Protodufourea
eickworti.Labiomaxillaryregionstronglypro-
jecting in lateral view (fig. 4) with labium
projecting well beyond apex of maxilla.
Maxilla with dorsal surface spiculate; cardo,
stipes evident but not pronounced; articulat-
ing arm of stipital sclerite not evident;
maxillary palpus moderately large, longer
than basal diameter, arising from maxillary
apex. Labium strongly divided into premen-
tum and postmentum, moderately long; pre-
mental sclerite not evident; labial palpus
subequal in size to maxillary palpus. Salivary
lips projecting, transverse, moderately narrow
infrontalview(figs. 3,13);asseenwithSEM,
upper and lower lips with apical fringe of
papillae (figs. 14, 15); lower lip with internal
surface consisting of parallel longitudinal
ridges; upper lip with internal surface without
such ridges but with scattered papillae.
Hypopharynx protuberant, spiculate toward
mouth, not longitudinally grooved; hypopha-
ryngeal groove absent, so that hypopharynx
curving onto labial apex.
BODY: Integumentwithfinescatterednon-
setiform sensilla and with spiculate areas
laterally behind head and toward rear of
abdomen; some dorsal body tubercles faintly
wrinkledapically,thoseofabdominalsegment
3 and 4 somewhat flattened apically on
postdefecating (but not predefecating) larva
(see ‘‘Discussion of Relationships’’). Body
form (figs. 1, 2) moderately robust; interseg-
mental lines moderately weakly incised on
Figs. 18–20. Dufourea a. australis. 18. SEM
predefecating form; on postdefecating form
micrograph of postdefecating larva that had been
clearedbeforebeingcriticalpointdriedandcoated, ventral intersegmental lines, particularly of
showingmouthparts,withrightmandibleremoved, abdomen, deeply incised; paired prothoracic
approximate frontal view. 19. Same, close-up of dorsal tubercles present, smaller than those of
salivary opening. 20. SEM micrograph of inner mesothorax,metathorax,andmostabdominal
surface of cocoon showing one end of blackish segments (figs. 1, 2); all tubercles conical (not
object of unknown origin and silk strands of
transverse); abdominal segment 9 strongly
variable diameters; for photograph, see fig.23; for
produced ventrally; abdominal segment 10
discussion,seetext.
positioned dorsally on 9 as seen in lateral
2008 ROZEN AND O¨ZBEK: IMMATURESOFROPHITINE BEES 9
view(figs. 1,2);onpredefecatinglarva(fig. 2), extremely narrow salivary lips (fig. 10), of D.
ventral integument of segments 9 extended, a. australis are the most reliable and easily
causing segment 10 to be partly tilted and used diagnostic feature.
making anus appear dorsal on 10; on post- HEAD (fig. 10): Integument as described
defecatinglarva(fig. 1),ventralintegumentof for Dufourea holocyanea.
segment 9 strongly retracted. Spiracles small, Head (figs. 10, 11, 18, 19) size and width,
those of thorax slightly larger than those of and tentorium as described for Dufourea
abdomen,thoseofpredefecatinglarvawithout holocyanea.Postoccipitalridgewelldeveloped,
sclerites, not on tubercles, those of postdefe- not becoming weaker toward vertex, in
cating larva on low tubercles composed of contrast to D. holocyanea and D. mulleri;
presumably thick chitin surrounding atrium other internal head ridges as described for D.
(these tubercles so low as to be easily holocyanea. Parietal bands evident as integu-
overlookedonspecimensthatarenotstained); mental scars. Antennal features as described
peritreme (figs. 5, 17) present, narrow; atrium forD.holocyaneaexceptpapilla(fig. 11)more
projecting slightly beyond wall, with rim, elongate, its length nearly equal to basal
globose; atrial wall smooth; primary tracheal diameter. Vertex and labrum as described for
opening with collar; subatrium normal in D. holocyanea.
length, consisting of about 12 chambers. Mandible similar to that of Dufourea
Male with median, transverse, integumental holocyanea except tubercles on outer mandib-
scar ventrally near apex of protrusion of
ular surface smaller, less conspicuous.
segment 9 of predefecating larva but closer
Labiomaxillary region as described for D.
toposteriormarginofsegmentofpostdefecat-
holocyanea including absence of articulating
inglarva;femalesexualcharactersvisibleonly
arm of stipital sclerite and premental sclerite.
on some predefecating larva as pair of small,
Salivary lips projecting, transverse, extremely
pale, subcutaneous imaginal discs arranged
narrow in frontal view (figs. 10, 18), so that
ventrally on each of abdominal segments 7, 8,
their apical width no greater that distance
and9,withthoseof7farthestapartandthose
from their base to base of labial palpus.
of 9 closest.
Hypopharynx as described for D. holocyanea.
MATERIAL STUDIED: 3 postdefecating, 6 BODY: Integument with fine, scattered,
predefecating larvae, USA: Washington:
nonsetiform sensilla and with finely spiculate
Kittitas Co.: 21 km N of Yakima, between
areas laterally behind head, toward rear of
Yakima River and Highway 821 at 10.5 mi
abdomen,andonmanydorsalbodytubercles;
mark, June 2000 (E. Miliczky); 4 last larval
some dorsal body tubercles faintly wrinkled
instars, same except 15 km S of Ellensburg,
apically and somewhat flattened apically,
along Umtanum Creek, 2 km W Yakima
suggestingapicesoftuberclessubject todefor-
River, July 1996.
mation when larva resting on them (but see
REMARKS: Eugene Miliczky is preparing a ‘‘Remarks’’ in treatment of Protodufourea
manuscript on the nesting biology of this
eickworti). Body form, intersegmental lines,
species,specimensofwhichhekindlydonated
and dorsal body tubercles as described for
for this study.
postdefecatinglarvaofD.holocyanea.Spiracles
small, subequal in size, otherwise similar to
Mature Larvae of Dufourea australis australis thoseD.holocyaneaexceptsubatrialchambers
Michener may be numerous. Male with median, trans-
Figures 10, 11, 18, 19 verse integumental scar ventrally close to
posterior margin of segment 9 of postdefecat-
The mature larva of this species is known inglarva;femalesexualcharactersunknown.
only from the postdefecating form. MATERIAL STUDIED: 2 postdefecating lar-
DIAGNOSIS: Although there are several vae, USA: Arizona Pima County: Desert
subtle differences distinguishing the postdefe- Station, E. side of Tucson Mts., April 28,
cating larva of this species from that of 1993 (J.G. Rozen); 12 postdefecating larvae,
Dufourea holocyanea (as indicated in the same except May 1, 1993; 7 postdefecating
following description) and D. mulleri, the larvae, same except May 10, 1993.
10 AMERICAN MUSEUMNOVITATES NO. 3609
REMARKS: JGR discovered nests of 5.5 mm, length 6.0–6.5 mm, N 5 8). Cell
Dufourea a. australis on the steeply sloping closures(fig. 22)wereevenspiralsoffourcoils
(but not vertical) bank of a ravine at Desert to the radius, concave on the inside, with a
Stationin1993.HevisitedthesiteonApril28, diameter of 2.5–3.0 mm, and on the outside
May 1, and May 10, when the following brief smoothly concave with an even surface. The
observations were recorded. These observa- closures were about 0.5–0.8 mm thick in the
tions are augmented with others made during middle where the outer and inner surfaces
the preparation of the current paper on cells approachoneanotherbutmuchthickeronthe
preserved in 1993 and retained in the collec- periphery.
tion of the AMNH. Completed cocoons ofDufourea a.australis
One main tunnel and presumably others (itscleptoparasitedoesnotspincocoons)were
were open and 4 mm in diameter. Numerous very thin and adhered tightly to the cell wall,
cells were scattered about 15 to 20 cm deep so that the cocoon fabric could not be pulled
into thebank.Whenfirst studiedon April 28, away from the wall. The cocoon completely
theyconsistedofvacatedcells,representingan filledthecelllumen;itsshapecorrespondedto
earlier generation, and cells occupied by theinternalshapeofthecell.Theinnersurface
feeding and diapausing larvae of both D. a. was slightly shiny, thereby contrasting with
australis and its cleptoparasite, Neopasites the dull cell wall before cocoon construction.
cressoni Crawford (Apidae: Nomadinae: Insomecells,thecocoonwassemitransparent,
Biastini). When examined on May 10, all so that feces and tan substrate indistinctly
larvae were postdefecating, an indication that showed through. In these cases, the cocoon
both D. a. australis and N. cressoni are gradually became opaque and paler toward
univoltine. Cell walls (figs. 21, 22) were thick, the front end, and at the closure, its inner
often 0.5 mm or more on sides and rear, surface turning white (fig. 23). In other cells
harder than the substrate, and could be the cocoons were more uniformly pale and
extracted intact from the ground as small opaque. The cocoon fabric was a single layer;
hard nuggets. Female D. a. australis presum- individualsilkstrandswereusuallynotclearly
ably impregnated the wall with a hardening identifiable under stereomicroscopic examina-
substance, possibly nectar. When submerged tion.UnderSEMexamination,whitefabricat
in water, a piece of cell wall started to theclosureendseemedtoconsistofextremely
disassemble immediately and completely fell fine, crisscrossing silken strands as well as
apart in a minute, as would be expected if the some coarser strands (fig. 20). In many cells
hardening substance were nectar.5 The inner uniformly shaped, elongate, blackish objects
surfaceofthewall(fig. 21)wasdull,even,but (figs. 20, 23), about 0.4 mm long, were scat-
with small projecting soil particles, and was teredontheinnersurfaceofwhitishsilk.Their
unlined, contrary to the reflective cell linings flattened shapes suggested that they had
of most bees. When the cell wall disassembled desiccated.Althoughtheiruniformityofshape
in water, the inner surface may have had suggestedthattheymighthavebeeneggs,they
slightlymorecohesion,possiblyresultingfrom showed no discernable microstructure under
compression of very fine particles by some highSEMexamination(fig. 20).Theiridentity
action (tamping?) by the female. Cell shape, and source are unknown.
like that of other rophitines, was symmetrical In cells examined before cocoon construc-
around its long axis, with floor and ceiling tion, feces were deposited longitudinally as
equally curved in side view, and wide com- elongate flattened yellowish stripes6 from the
pared with its length, measure from rear to rear of the cell partway toward the closure
center of closure (maximum diameter 5.0– end,sothattherear2/3sto3/4softhecellwall
5Nectar has been suspected to harden the cell wall of 6ThefecaldepositionofDufoureaa.australisshouldnot
another but distantly related ground nesting bee, be confused with that of its cleptoparasite, Neopasites
Ashmeadiella holtii Cockerell (Megachilidae) (Rozen, cressoni.Withthelatterspecies,thefecalpelletsaremuch
1987), and has been definitely identified as forming part shorter,sothattheyappeartobedabbedontherearcell
(i.e., mixed with masticated leaves) of the cell lining of surface (fig.26), giving the appearance of polka dots
another member of that genus that nests in preformed distributedoverthesurface,and,aswithallNomadinae,
cavities(RozenandEickwort(1997). theyarenotcoveredbyacocoon.