Platyhelminthes from salt marshes of Coomera River, southeastern Queensland, Australia

9 Pages·2001·4.3 MB·English

PLATYHELMINTHES FROM SALT MARSHES OF COOMERA RIVER,
SOUTHEASTERN QUEENSLAND, AUSTRALIA
ANNO FAUBEL AND BRONWYN CAMERON
Faubel, A. & Cameron, B. 2001 06 30: Turbellaria from salt marshes ofCoomera River,
southeastern Queensland, Australia. Memoirs ofthe Queensland Museum 46(2): 511-519.
Brisbane. ISSN 0079-8835.
Three new species, Chitdianea coomerensis gen. et sp. nov. (Acoela), Macvostomum
greenwoodisp. nov.andMacrostomumcoomerensissp. nov.(Macrostomida)aredescribed
from the brackish water estuarine area of the Coomera river, Gold Coast, Queensland,
D
Australia. Taxonomy, morphology,fiatworms, Acoela, Macrostomida.
DrA. Faubel, InstitutfurHydrobiologie unciFisehereiwissensehaft, L'niversitdt Hamburg,
Zeiseweg 9, D-22765Hamburg, Germany(e-mail:[email protected]); B. Cameron,
The UniversityofQueensland, StLucia 4072, Australia; 14 March 2000.
The Australian fauna o( Acoela and were suspended above the tank to attract
Macrostomida of limnetic, brackish and marine organismsintothewatercolumn. Everyhour, the
habitatsisnotverywell known. Overa longtime tank was siphoned through a 63|im sieve to
the only study known on Acoela was carried out collectemergedfauna.Thedefaunatedwaterwas
by Haswell (1905) on Helerochaerus australis. then returned to the tank and the extraction
More recently, however, more intensive studies process repeated until the majority of the
&
have been started by Trench Winsor 1987 on organisms had been collected. Sexually mature
Amphiscolops sp. and Haplodiscus sp. (in part specimens ofTurbellaria were studied alive and
Waminoa IHits Winsor, 1990), Winsor 1988 on in squash preparation, i.e. flattened under the
Wulguru cuspidata, Winsor 1990 on increasing pressure of the coverslip as the
Conyolutriloba hastifera, Waminoa litus, W. sp. preparation dried. Measurements of living
1, and W. sp. 2. organisms (m.l.s.) were made from squashed
A first census of macrostomid species of ones. These measurements are given in
Australiaby Faubel etal. (1994) listed 6 species. parentheses in the running text. All other
Ofthese Macrostomum titha v. Graff, 1882 and measurements were made from sections of the
Promacrostomumpalttm Sluys, 1986 are known holotype. Forhistologicalobservationspecimens
from freshwater environments. Dunwichia were relaxed in 7% MgCI2 and fixed in Bouin's
arenosa Faubel, Blome & Cannon, 1994, fixative. Specimens were embedded in Paraplasl
Bradburia australiensis Faubel, Blome & plus(Reichert&Junk)andcutsagittallyat3.0um
Cannon, 1994, Macrostomum australiense andstainedwithhaematoxilin-eosinaccordingto
Faubel, Blome & Cannon, 1994, and Macro- Mayer. Types are deposited in the Queensland
stomum sp. Faubel, Blome &. Cannon, 1994, Museum, Brisbane.
however,areallknown fromeulittoralhabitatsof SITE DESCRIPTION
sandy beaches of Stradbroke Island, South
Queensland. Coomera salt-marsh (27°54'S, 153°17'E) was
In the present paper one acoelous species and chosenasasiteforturbellariancollection.Forthe
two macrostomid species from brackish water past 4 years this site had been excluded from the
habitats are described. broad-scale mosquito control measures that
METHODS typically occur in southeast Queensland. It was
therefore considered to be a relatively pristine
For studies on meiobenthos, sediment was site.
qualitatively collected from the Coomera Coomera salt-marsh is only inundatedby tides
salt-marsh pools. The freshly collected sediment of 2.4m or more above datum. Salinity ranges
was transferred into a glass tank in a constant between 25-38 ppt. The salt-marsh pools are
temperature K.om approximating ambient 2-7nr in area and are bordered by dense clumps
conditions (Salinity ca 30 ppt, 27°C). Habitat ofSporobolus virginicus (Kunth.) the dominant
waterwas added to the sediment tank, to a depth marsh-grass, and Sarcocornia quinqueflora
of about 15cm. A series of 60 watt light bulbs Bunge (ex. Ung. Stern) a sprawling herbaceous
512 MEMOIRS OF THE QUEENSLAND MUSEUM
halophyte.The sedimentconsists ofmuch highly Childianea coomerensis sp.nov.
organic mud with negligable amounts ofsand. (Figs 1A-B, 2)
SYSTEMATICA ETYMOLOGY. From theCoomera Riverestuary on the
Gold CoastofQueensland.
Order ACOELA Uljanin, 1870
Family CHILDIIDAE Dorjes, 1%8 MATERIAL.HOLOTYPE.Coomerasalt-marsh(27°4'S,
QM
153°17'E), Gold Coast, southeast Queensland,
Childianea gen. nov. G217362, 2 specimens, May 1998 leg. B. Cameron.
DESCRIPTION. Length of body of living
DIAGNOSIS. Childiidae with frontal organ. sexually mature specimens up to 0.9mm, when
Body wall musculature with outer circular and extended and gliding; maximum width up to
innerlongitudinalmusclefibers. Separategenital 0.18mm in second halfofbody, area ofgrowing
openings. Seminalbursawithvaginaandcellular oocytes. Body spindle-shaped with rounded
bursamouthdirectedanteriad. Pairedovariesand frontal and rear body end, dorso-ventrally
testes. Male copulatory apparatus without flattened. Posterior body end with a small
seminal vesicle; proximal ejaculatory duct with
vacuole being horseshoe-like (Fig. 1A). In
sclerotised layer working as penial stylet; distal transmitted light, colour ofbody yellowish but
ejaculatory duct with prostatic glands. False
digestive parenchyme and lumen bright yellow
seminal vesicles present.
through ingested diatoms. Glandular duels o\"
TYPE SPECIES. Childianeacoomcrensissp. nov. frontal organ open to exterior through several
pores at the frontal end, the glands ofwhich lie
ETYMOLOGY. Derived from thegeneric name CMldia. posteriorto the statocyst. Secretion ofthe glands
coarsely granulated. Statocyst embedded within
KEY TO THE GENERA OF THE
the medio-frontal brain, about 55|im (m.l.s.)
CHILDIIDAE distant from anterior body end. Epidermal cells
1. withsinglemalecopulatoryorgan 3 2.0 - 2.5|im high, with intraepithelial nuclei;
rhabdoids lacking. Epidermis completely
withseveralmalecopulatoryorgans 2
covered with cilia 3.5 - 4.0uin in length. Body
2. with2malecopulatoryorgans . . Ckiidiav.Graff,1910 wall musculature with faint outer circular and
with4 mulecopulatory organs
TetraposthiaAnDerLan, 1936 inner longitudinal fibers. Dorsal and ventral
subepidermal hyaline glandsopen to the exterior
3(1).bu.rs.awithsinglemalecopulatoryorgan;withoutsemina4l throughout body surface, more abundant lateral.
Digestive lumen bordered by nucleus-rich
withseminalbursa 6
4. withoutmaleatriumorveryshort 5 parenchymal tissue which starts immediately at
withlongmaleatrium ttriofrontaD&rjes,1968 level of frontal glands and fills the whole
mid-bodycoveringtheovariesdorsal. Gut lumen
5. copulatoryorganwithsclerotisedspines
ictinoposthiaAnDerLan,1936 tilled with diatoms and detritus. Mouth ventral
copulatory organ with rosette like muscular elements behind mid-body, about 400um (m.l.s.) distant
encasingtheseminal vesicle from frontal body end.
ParaprvporusWestblad,1945 Reproductive system (Eig. 2). Lateral testes
6{3).awnidthinsneemrinlaonlgbiutrusdai;nablomduysmculsecfliebewrasllwithoutercircula7r situatedabout 180um (m.l.s.) from anteriorbody
end. Spermatids penetrate the parenchyma on
body musclewallwith inversemuscle la\ers
ParaphanostomaStQiTibQck,1931 both sides lateral ofthe ovaries. Anterior to the
7. withbursano/zle 8 transverse level of the male complex the
withoutbursanozzle PseudaetmopasthiaDtfrjzSi 1968 spermatids accumulate in two false seminal
. vesicles which enter the common proximal
8. bursanozzledirectedanteriadorcaudad 9
ejaculatory duct in common. True seminal
bursa nozzle invaginated in theseminal bursa
PelophilaDQr)Q$ 1968 vesicle lacking. Ejaculatory duct is closed by a
9. bursanozzlecellular t 10 sphincter atjunction ofthe vasa deferentia. The
10. mbuarlseancoozmzlpelescxlerwoittihsedpr.os.taPthiiclagcltainndopso,stwkiitahDioSuxtjesse,m1i9n6a8l rveeanrtrablodmayleenpdo,rele(Faidgs.t1oB,t2h)e, 3b2ulubmoudsistpaynrtiffroormm
vesicle Childianeagen.nov. copulatory organ. Musclebulbahighly muscular
male complex with seminal vesicle, without prostatic complex 43um in length with central ejaculatory
glands irchactinoposthiaD&rjes*1968 duct (Fig. 2). The muscle fibers run more or less
PLATYIIELMINTHKS FROM THE COOMERA RJVER 5L3
oc
FIG I. Childiuimt coomerensis^ gen.et sp.nov. A, dorsal \icu in squash preparation. B, diagrammatic sagittal
reconstruction afterserial sections. Scale: 200p.m. (b = brain, bs = seminal bursa, hm = mouth ol bursa, ca =
copulatoryapparatus,dl rdigestivelumen, F= frontalorgan,fs=falseseminalvesicle,in=mouth,o=ovary,oc
= oocyte, s = statocyst. t = testis, v = vacuole, 6 = malegonopore. 2 - female gonopore).
parallel, inclining toward the ejaculatory duct, sclerotised epithelial layer looking stylet-like;
and obvious! function as retractors during distal part is ]2Mm long, not ciliated, and of
copulation. Ejaculatory duct tripartite; proximal
prostatic function. Cell bodies ofepithelial layer
spacrlterooftisdeudctf(oFrimgi.ng2) aabsoeuatl 1c(o)nj.tirmollloinngg, hsipgehrlmy very elongated, enclose copulatory complex
ejaculation; central one. 31um long, lined by a (Fig. 2).
514 MEMOIRS OF THE QUEENSLAND MUSEUM
FIG. 2. Childianeacoomerensis,gen.etsp. nov.; sagittal reconstruction ofthemaleand femalecomplex. Scale:
50|im. (bs = seminal bursa, bm = mouth ofbursa, c =circularmuscles, dl = digestive lumen, ej = ejaculatory
duct, fs=falseseminal vesicle, 1 = longitudinal muscles, n - nucleus,oc=oocyte, po=prostatoidglands, re =
retractormuscles,se=seal,sg^subepidermalgland,v—vacuole, 6 =maiegonopore, V =femalegonopore).
Female system with paired ovaries and a as a pointed stylet. On the basis ofthis character
seminal bursa. Oogonia of each ovary lie the species belongs to the Childiidae. Coomera
ventro-lateral, 190-200um behindstatocyst (Fig. coomerensis,however, differsfrom all speciesof
IB). A line of growing oocytes runs latero- the known genera ofthe family Childiidae in the
caudad. Hindmost oocytes are about I70um presence of prostatic glands entering the distal
(m.I.s.)distant from posteriorbodyend. Seminal ejaculatory duct. In combination with the
bursawithadistal ciliatedatrium(7.5um long),a characters ofpresence ofa seminal bursa with a
central vesicle filled with sperm (20jim in cellular spermiducal duct directed frontad and
diameter),andacellularmouthpiece 13um long. absence ofa true seminal vesicle, establishment
The atrium rises dorsad, 65urn anterior to male of monotypic Childianea and its species C.
pore, widening proximad to form avesicle filled coomerensissp.nov. isjustifiedwithinthefamily
with sperm. The cellular bursa mouth piece is Childiidae.
directed anteriad, reaching central the hindmost
vpaersticolfetohfebouorcsyateiss.cAlpoesretdubryeabestpwhienecnteart.rium and FOarmdielryMMAACCRROOSSTTOOMMIIDDAA,EMeViaxnneBre,ne1d9e2n4,
1870
DIAGNOSIS. With characters ofthe genus.
Macrostomum greenwoodi sp. nov.
DISCUSSION. The family Childiidae was
(Fig. 3)
established and discussed in detail by Dorjes
1968. Up to now the family contains 10 genera. ETYMOLOGY.NamedinhonourofProf.J.Greenwood,
Dorjes included in this family all these generaof University ofQueensland.
Acoela which have species with a sclerotised
MATERIAL. HOLOTYPE. Coomera salt-marsh
(cuticular according to Dorjes 1968), muscular,
f27°54,S, 153°17'E>, Gold Coast southeast Queensland,
oinrctelhleulasrepmeinniaslplvuegswichliec.h iTshneevenreiwnvasgpiencaiteesd QMG217363,2specimens,April 1998leg.B.Cameron.
Childianea coomerensis is characterized by a DESCRIPTION. Length of body of living
sclerotised ejaculatory duct obviously working sexually mature specimens up to 1.3mm, when
PLATYHELMINTHES FROM THE COOMERA RIVER 515
ra B
a m
pg
N
--,
VS
ad
FIG. 3. Mucrosiomum greemvoodi, sp. nov. A, dorsal view in squash preparation. B, male stylet. C, sagittal
reconstructionofthefemaleorgan.Scales: A,200um;B,20jim;C,50um.(ad=adhesiveglands,b=brain,bs=
seminalbursa,c=circularmuscles,ce=cementglands,d=diatoms,ds=spermiducalduct,e=eyes,fa=female
atrium, = intestine, = longitudinal muscles, m =mouth, n =nucleus, o= ovary, pg= pharyngeal glands, r=
rhabditc.i ra = rhammitIes. t=testis, vg= vesiculagranulorum,vs = seminal vesicle, o = malegonopore. 5 =
femalegonopore).
516 MEMOIRS OF THE QUEENSLAND MUSEUM
extended and gliding; maximum width up to of a ciliated atrium (11.4p,m long), a bursal
0.18mm in mid-body. Outline of body with vesicle (37.9f.im long), and a spermatic duct
characteristic macroslomid like anterior end; (12.8u.rn long). Thebursal vesicle is totally lined
posterior end rounded, provided with strong with elongated cells. The proper epithelium of
adhesive glands (Fig. 3A). Around margin weak the bursa looks syncytially in which the
sensory hairs of varying length and stiffness surroundingcells(upto35um)excreteobviously
present. In incident light body brownish with coarsely granulated secretion. Cement glands
darkercontrastingoocytes intheposteriorpartof surrounding the female pore, discharge their
body; gut intensively coloured yellow based on secretion into the female atrium.
the uptake and consumption of bright yellow
diatoms. Eyes present, 175um (m.l.s.) far from DIAGNOSIS. The species is diagnosed on the
outline ofthe male stylet (Fig. 3B).
anterior margin of the body. Crescentic brain
169u,m (m.l.s.) distant from anterior end. Macrostomum coomerensis sp. nov.
Rhammite glands open ventro-frontal through (Fig. 4)
the anteriormargin ofbody, theircells extending
posteriad up to the level ofthe pharynx simplex. ETYMOLOGY. From the Coomera river of the Gold
In mid-body cells of epidermis 4.6u.m high CoastofQueensland.
covered with 4.0 to 4.6jim (ventral) and 3,4 to MATERIAL. HOLOTYPE. Coomera salt-marsh
3.9um (dorsal) long cilia. Intraepithelial nuclei (27°54'S, 153°17*E) Gold Coast, southeast Queensland,
present; rhabdites about 9.0u.m long, the cell QM G217364, 2 SPARATYPES. Same data, QM
bodies of which subepidermal, up to 11.3um G217365-366, numerous specimens, April 1998 leg. B.
long. Rhabdites distributed in longitudinal rows Cameron.
over the dorsal and ventral body surface. Body
muscle wall with outer circular and inner DESCRIPTION. Length of body of living
longitudinal muscle fibers. Basal membrane not sexually mature specimens up to 1.4mm, when
observed. Digestive system with pharynx extended and gliding; maximum width up to
simplex pierced by extrapharyngeal glands and 0.25mminanteriorpartofsecondbody-half,area
large intestine but less numerous ciliated than ofoocytes(Fig. 4A). Anteriorandposteriorbody
pharynx. The intestine tillsthemedianpartsover end rounded. Marginal hairs or spines absent.
the ovaries, oocytes, and seminal bursa and Frontal glands present, not reaching anterior
extends caudad up to the seminal vesicle. Mouth level ofbrain. Eyes present immediately behind
behind brain, 210p.m (m.l.s.) distant from crescentic brain, 125um (m.l.s.) distant from
anterior end. The species feeds on diatoms and anterior margin ofbody. In incident light colour
detritus particles. Ingested sand grains covered brownish yellow with contrasting darker lateral
with detritus are abundant. Excretory system not ovaries. In transmitted light body greyish
observed, probably absent. Male and female translucent with yellowish digestive system.
gonopores separate, 185u.ni (m.l.s.) distant from Mouth opening immediately caudal of eyes.
each other. From mouth the pharynx simplex rises dorso-
caudad and receives openings of digestive
Reproductivesystem (Fig. 3). Themalesystem is glands. Intestine with less numerous cilia. The
typicallymacroslomidlike. Itconsistsofbilateral gut fills the median parts ofthe body extending
testes, vasa deferentia running caudad to either caudadoverovariesandoocytes,endingupatthe
side ofthe intestine and ovaries, a common vas anterior level of the last oocytes. Rhabdites
deferens, a seminal vesicle, a prostatic vesicle, evenly distributed in serial lines over the body.
and a male stylet which projects into the short Ventral rhabdites 7,5u.m and dorsal ones 9.4u.m
male antrum. The stylet depicted in Fig. 3A, is long. Reardorsalbodyendwithdenseaggregates
98.3p.rn long; the proximal openingis I2.0um in of large rhabdites (10.7u.rn long). Ventral
diameter; the distal opening is subterminal.The epidermisis 5.7(im thick anddorsaloneis 2.8pjn
male pore is 105u.ni (m.l.s.) distant from rear thick, entirely covered with 5.7um long cilia;
body end. The antrum rising dorsad is 10.Sum epithelial nuclei subepidermal. Basal membrane
long. not observed. Body muscle wall with outer
The femalesystem consistsofbilateral ovaries circular and inner longitudinal muscle fibers.
and a seminal bursa. The ovaries forming lateral Excretory system notobserved,probably absent.
fieldsofoogonia,liebehindthegerminativezone Gonopores separate, 65um distant from each
of the testes in mid-body (Fig. 3A), generating other. Bilateral testes anterior to ovaries; last in
caudad large oocytes.The seminal bursaconsists mid-body.
PLATYHELMINTHES FROM THE COOMERA RIVER 517
B
-—oc
FIG 4. Macrosiomum coomerensis, sp. nov.; A, dorsal view in squash preparation. B, male stylet. C. sagittal
reconstructionof"the femaleorgan. Scales: A, 200um; B,C\ 5Uum. (b=brain, bs-seminal bursa,c-circular
muscles,ce=cementglands,ds-spermiducalduct,e=eyes, F=frontalorgan,fa=femaleatrium,i=intestine, I
=longitudinalmuscles, m mouth, n nucleus, a ovary, pg = pharyngeal glands,r=rhabdite.t=testis,va=
vaginas vg = vesicula aranulorum. vs = seminal vesicle, i = male gonoporc. 5 = female gonopore).
Reproductivesystem(Fig. 4). Themalesystem is testes, vasa deferentia running caudad to either
typicallymacrostomidlike.ltconsistsofbilateral side ofthe intestine and ovaries, a common vas
518 MEMOIRS OF THE QUEENSLAND MUSEUM
deferens, a seminal vesicle, a prostatic vesicle, Beklemishev (1951) has assigned the species of
and a male stylet which projects into the male Macrostomum to3 taxonomicgroupsas follows:
antrum. The sac-like testes are located 100 to Macrostomum hystricinum group (stylets being
llOum (m.l.s.) behind the pharynx. Latero- funnel-like proximally, with tapered hook-like
caudal of the female bursa the vasa deferentia shapedistally),Macrostomumorthostylumgroup
unite to a common vas deferens on the left side (stylets being straight or curved, distad evenly
before entering the seminal vesicle. The distal tapering), and Macrostomum tuba group (stylets
part ofthe seminal vesicle, the prostatic vesicle, having a distal characteristic Macrostomum
and the proximal part of the penial sheath in ////?</-like enlargement, with the opening of the
which the stylet rests, are covered with a ejaculatory duct in the centre of the tip. or
complicated system of strong muscle fibers. subterminally). Although these groupings are
These fibers are responsible for protrusion and useful in a taxonomic sense, they should not be
retraction ofthe stylet and ejaculation ofsperm regarded as phyletic groupingsbecause there are
into the female system. The distal part of the different lines ofthe development ofthe female
prostatic vesicle is encased in the proximal genital organs within each group. A revision of
portion of the stylet being slightly funnel-like the taxon Macrostomida is in preparation by the
extended. The stylet is 125um (m.l.s.) long; the first author. Based on the distal features ofthe
distal two thirds arc spiralled as outlined in Fig. stylet, Macrostomum coomerensis belongstothe
4B. The distal tip ofthe stylet is broadend, the Macrostomum tuba group and Macrostomum
opening of which lies subterminally. The male greenwoodi to the Macrostomum orthostylum
pore,42.7j.imdistant from therearbodyend leads
group.
antero-dorsad to a rather long male antrum
(15.2um). Macrostomumcoomerensisischaracterisedby
The female system consists ofbilateral ovaries having the male stylet formed like a cork-screw
and a seminal bursa. The oogonia generate with a distal enlargement, and a subtenninal
laterally immediately behind the testes and are opening ofthe ejaculatory duct. On the basis of
growingupcaudad formingoocytes oneach side these features the species belongs to the
ofthe body. The female genital pore is 280(.im Macrostomum tuba group. Macrostomum
(m.l.s.) distant from the caudal body end. The species with a spiral stylet are: M. leprasAn Der
female atrium (43.5um long) entered by cement Lan, 1939, M. lewisi Ferguson, 1939. M.
glands,isoutlinedwithciliaandrisesdorsad.The reynoldMsi Ferguson, 1939, M. riedeli Ferguson,
transition to the vagina is closed by a sphincter. 1940, delphax Marcus, 1946, M. contorlum
The vagina, up to 31.5urn long, ciliated, extends Beklemishev. 1951, M. phytophilum
frontadtoform abursal vesicle filledwithsperm. Beklemishev, 1951, M.phocorum Marcus, 1954,
The cilia of the vagina up to 13.0uui long. M. spiraie Ax, 1956, M, poznaniense Kolasa,
Anteriad ofthe bursa a spermiducal duct (24mn 1973, M, bicurvistyla Armonies & Hellwig,
long) ispresent.Thespermiducalductreachesup 1987. and M. extracu/um Ax & ArmMonies, 1990.
mediad to the level of the last oocytes. The Of these species, however, only leptos, M.
epitheliaofthevagina,thebursal vesicle, andthe reynoldsi, and M, extraculum have the
spermiducal duct are cellular with intraepithelial characteristic distal enlargement of the stylet
nuclei. which assigns them to the Macrostomum tuba
group. The other species listed above belong to
DfAGNOSlS. The species is diagnosed on the the Macrostomum orthostylum group.
outline ofthe male stylet (Fig. 4).
Macrostomum coomerensis, M. reynoldsi. M.
DISCUSSION. Macrostomidae currently contains extraculum, and M. leptos are differentiated by
11 genera. The dominant taxonomic characters the different length and outline oftheir stylets.
concernthemaleeopulatoryapparatus: adistally The stylet ofM. coomerensis (125urn in length)
armed ejaculatory duct (stylet), or an unarmed isessentiallylongerthanthatofbothM. reynoldsi
cirrus. Genera having a penial stylet are Macro- (72um) and M. extraculum (68-72u.m). For M,
stomum Schmidt, 1848, Omalostcmum Van leptos, only the length ofthe body (0.8mm) and
Beneden, 1870, Promacrostomum An Der Lan, the outline ofthe stylet are known. The stylet of
1939, Archimacrostomum Ferguson, 1954, M. leptos differs greatly from that of M.
Bradynectes Rieger, 1971, and Bradburia coomerensis both in the nature of the distal
Faubel,Blome& Cannon, 1994. Ofthesegenera, swellingwith subtenninalpore and inhavingthe
Macrostomum has the most species (127). proximal and median part of the stylet greatly
PLATYHELMINTHES FROM THE COOMERA RIVER 519
curved. Distally, the stylet is only weakly Department, Prof. Jack Greenwood and stafffor
corkscrew-like. facilities and help, University of Queensland,
Macrostomum greenwoodi belongs to the Brisbane. Dr L.R.G. Cannon, Queensland
Macrostomum orthostylum group based on the Museum. Brisbane and Prof. K. Rohde,
University of New England, Armidale, NSW,
curved and evenly tapered distal region of the
stylet. Themain distinguishing characterforthis assisted with help and arrangements.
species concerns the outline of the distal LITERATURE CITED
termination of the stylet. The distal tip in M.
greenwoodi is obtuse, with a subterminal BEKLAErMalIseSeHs.EVZ,uglVe.iNc.h e1i9n27B.eiCtrbaegrzudrieMoFrapuhnoalodgeys
ejaculatory duct opening. In this respect, and in und zur Systematik der Dalyellioidea.
nothavingacork-screwlikestylet,the followiMng ZoologischesJahrbuch, Systematik 54: 87-138.
9 species resemble with MM. greenwoodi: BEKLEMISHEV, V.N. 1951. The speciesofthe genus
curvituha Luther, 1947, infundibuliferMum Macrostomum (Turbellaria, Rhabdocoela) ofthe
Plotnikov, 1905, M. johni Young, 1972, USSR[inRussian]. Bulletinofthenatural Society
longituba Papi, 1953, M. lutheri Beklemishev, ofMoscow(Biology, newseries) 56, 31-40.
1927, M. mediterranean* Ax, 1956, M. DORJES, J. 1968. D\e Acoela (Turbellaria) der
magnacurviiuha Ax, 1994, M. mosquense deutschenNordseekusteundeinneuesSystemder
Beklemishev, 1951, and M. ienuicauda Luther, Ordnung. Zeitschrift fur zoologische Systematik
M und Evolutionsforschune 6: 56-452.
1947. With the exception of lutheri and M. FAUBEL, A., BLOME, D. & CANNON, L.R.G. 1994.
greenwoodiall otherspecieshavestyletswiththe Sandy beach meiofauna of eastern Australia
ejaculatory duct opening subterminally on the (southern Queensland and New South Wales). I.
concave side of the stylet. The stylets of M. Introduction and Macrostomida
greenwoodi and M. lutheri have ejaculatory (Platyhelminthes). Invertebrate Taxonomy 8:
openings subterminally ontheconvex sideofthe 989-1007.
stylet. M. lutheri was established by HASWELL. W.A. 1905. Studies on Turbellaria.
Beklemishev (1927) only on the characteristic Quarterly Journal of microscopical Science 49:
425-467.
termination of the stylet. Other morphological TRENCH, R.K. & WINSOR, H. 1987. Symbiosiswith
characters are unknown. Therefore, the only
dinoflagellates in two pelagic flatworms,
main differential character resides in the Amphiscolopssp. and Haplodiscussp. Symbiosis
complicate enlargement ofthe distal termination 3: 1-22.
ofthe stylet. WINSOR, L. 1988. A new acoel (Convolutidae) from
the north Queensland coast, Australia.
ACKNOWLEDGEMENTS FortschrittederZoolo^ie/ProgressinZoology36:
391-394.
Financial support was given by the Deutsche 1990. Marine Turbellaria (Acoela) from north
Forschungsgemeinschaft to Dr A. Faubel. We Queensland. Memoirs of the Queensland
thank Prof. G. Grigg, Head of Zoology Museum 28: 785-800.