Table Of Content©EntomologicaFennica. 16 September2005
Scuttle flies (Diptera: Phoridae) of saline habitats
of the Gulf of Gdansk, Poland
EwaDurska, ElibietaKaczorowska&R.HenryL.Disney
Durska, E., Kaczorowska, E. & Disney, R. H. L. 2005: Scuttle flies (Diptera:
Phoridae)ofsalinehabitatsoftheGulfofGdansk,Poland.—Entomol. Fennica
16: 159—164.
Resultsofasurveyofthescuttleflies(Diptera:Phoridae)ofsalinehabitatsofthe
GulfofGdanskarereported. Withinthreestudyseasons(1999—2001), atten10-
calities representing coastal brackish and maritime habitats, 39 phorid species
were collected. Among these, 36 were new to these areas, andXenotriplzleba
dentistylata Buck was the first record for Poland. The dominance structure,
phenologyandabundanceofphorids ofsalinehabitats aredescribed.
E.Durska,MuseumandInstituteofZoology,PAS, Wilcza64, 00—679Warszawa,
Poland;E—mail.‘ [email protected]
E. Kaczorowska, Department ofInvertebrate Zoology, University ofGdansk,
Pilsudskiego46,81—378Gdynia,Poland;E—mail.‘[email protected]
R. H. L. Disney, UniversityMuseum ofZoology, Cambridge CB2 3EJ, United
Kingdom;E—mail.‘ [email protected]
Received23 October2002, accepted9November2004
1. Introduction the tides and rainfall. Its eggs, being in a con-
stantlyhighhumidity, areatypicallythin-walled,
Scuttleflies(Phoridae)areoneofthemostabun- seemingly because they are not exposed to the
dantfamiliesofDipteraand“theprimecandidate risk of desiccation. Records of scuttle flies in
forbeingthemostbiologicallydiverse familyof maritime habitats are otherwise sparse, apart
insectsontheplanet”(Disney 1990, 1994). One- from scatteredrecords andreports, such as pho-
quarteroftheca.3,000speciesdescribedoccurin rids and other Diptera trapped in the oil oozing
thePalaearcticRegion. fromadeadwhale(Cobert&Disney 1998).Mar-
The seashore is generally not regarded as a itimehabitats havenotbeensystematically sam-
suitable habitat for Phoridae, but the larvae of pledforPhoridae.
some New World species of Megaselia are InPoland,littleisknownaboutscuttlefliesof
knowntobeintertidalandthus abletocopewith salinehabitats. Szadziewski(1983),investigating
fluctuationsinsalinity(Saunders 1928, Cheng& Diptera ofthese areas, found only eight phorid
Hogue 1974). Disney (2002) reported that the species. All ofthesewere haloxenes i.e. species
EuropeanMegaseliayatesiliveswithinthevoids thatoccuranddevelopnumerouslymoreoftenin
ofthe first shingle ridge above high watermark specificnon-salinethaninsalinehabitats. Inthis
andthat its larvae are likely to be subjectedto a paper,wereportonthephoridsofthebeachesand
range ofsalinities following the fluctuations of coastalbrackishareas oftheGulfofGdansk.
160 Durska etal. ' ENTOMOL. FENNICAVol. 16
2. Material and methods 2001, 1—2 times aweek. Flieswere collectedby
sweeping (using an entomologicalnet) overwa-
2.1. Study area ter’s surface, algae washed ashore, soils, plants
overgrowing dunes and cliffs, and in halophyte
Materialwascollectedontenareas, representing communitiesgrowingnearthesaline-waterreser-
twotypesofhabitatborderingtheBalticSea—the voirs. All scuttleflieswerepreservedin75% al-
coastal brackish and marine habitats. The first cohol. Megaselta females were not identifiedto
areawas at the Bay ofPuck and Gdansk—Gorki species.
Wschodnie, and the second one was formedby Todescribethedominancestructureofcommu-
theeightbeachesadjacenttotheGulfofGdansk. nities, a dominance index (D) was used (Durska
The brackish area, viz. Gdansk—Gorki 2001):
Wschodnie (the coastal type), is situated at the
mouthoftheWisla Smialariver. The salinearea D=n/N* 100% (1)
beside the river comprises bulrushes, brackish
marshes and brackish meadows. The latter are wheren=theabundanceofagivenspecies,andN=
overgrown by halophytes such as Aster tripo— theaccumulatedabundanceofallphoridspecies.
lium, Triglochin maritimum, Glawc maritima, Thedominanceindex(D)wasusedto classify
andArtrl'plex hastatum var. salinarium. On the the species into fourclasses: (1) eudominant(over
stony dam, Aster tripolium, Atrl'plex hastatum, 15.0%), (2) dominant (flom 5.1% to 15.0%), (3)
Spergularia salina, Elymus arenarius, Solanum subdominant (flom 1.1% to 5.0%) and (4) acces-
dulcamara and Sonchus arvensts can be found. soryspecies(upto 1.0%).
Stonesintheriverbottomandfloodedpartsofthe
dam—wherematerialwasalsocollected—areco-
vered with algae Enteromopha sp. and Clado— 3.Results
phora sp.
ThefliesoftheBayofPuckwerecaughtover The material contained 230 phorid imagines. The
coastal waters, and in brackish marshes and phorid fauna of the saline habitats sampled
meadowsalongthewaterside. Thebaybanksare provedtobericher(39 speciesbelongto 11 gen-
coveredwithPhragmttescommunts,whereas on era)thanexpected, inviewofthelimitedcollect-
the meadows occur Trtglochtn martttmum, ingbymeansofnettingonly. Themostabundant
Atrl'plexhastatum var. salinum,Astertripolium, genusMegaselta was representedby 21 species
Glaux maritima and Spergularia salina (Szad— (onlymales,ca.60%ofthetotalcatch)(Table1).
ziewski 1983).
The fFlieswerecollectedin supralittoral and
epilittoralzonesoftheeightbeachessituatednear 3.1.Dominancestructure
Gdynia — Wzgorze Swietego Maksymiliana
(Gdynia—Wzgorze), Gdynia — Orlowo (UTM: The cumulative abundance of the three eu-
CF44), Sopot, Gdansk — Jelitkowo, Gdansk — dominant (M. subnudipennis, M. ignobilis, M.
Brzeino(UTM: CF43), Gdansk—GorkiWscho- pultcartacomplex)andonedominantspecies(M
dnie (UTM: CF52), Wladyslawowo (UTM: brevtcostalts) exceeded 60% ofthe total catch.
CF37)andUstka(UTM:XA25). Theseareasare Thesubdominantswererepresentedbyninespe-
flatandsandy,andonlythelocalitynearGdynia— cies (Fig. 1). Among the species ofthe lowest
Orlowo, adjacentto thecliffs, is alittle stony. abundance, one male of Xenotrt'phleba denti—
stylata(Buck, 1997)wascollectedin27thofMay,
onthebeachnearGdynia—Brzezno. Itisthefirst
2.2.Phoridsampling, and statisticalmethods recordforPoland.
PhoridswerecollectedfromthebeginingofMay
totheendofSeptemberin 1999andfromthebe-
ginning of April to mid October in 2000 and
ENTOMOL. FENNICAVol. 16 ° Scuttleflieson the GulfofGdansk 161
Table 1. Speciescomposition, abundanceand phenologyofPhoridaeinsalinehabitatsoftheGulfofGdansk
(1999—2001). *=speciesnewtothe Polishfauna
Specimens/month
Species Larvalfeeding IV V VI VII VIII IX X total %
1 Borophagafemorata (Meigen) unknown — — — — — 1 — 1 0.43
2 Borophagasubsultans(Linne) unknown — — — 6 — — — 6 2.61
3 Conicera dauci(Meigen) saprophagous — — — 2 — 1 — 3 1.30
4 ConicerafloricolaSchmitz saprophagous — — — 1 — — — 1 0.43
5 Conicerasimilis(Haliday) necrophagous — — 1 — — — — 1 0.43
6 ConiceraschnittmanniSchmitz saprophagous — — — — 1 — — 1 0.43
7 Dorhniphora cornuta polyphagous — — — 1 — — 1 0.43
(Bigot in De La Sagra)
8 Diplonevranitidula (Meigen) zoophagous — — — — — 1 — 1 0.43
9 Gymnoptera vitripennis(Meigen) zoophagous — — — 1 — — — 1 0.43
10 Megaselia aculeata (Schmitz) ?saprophagous — — 1 — — — — 1 0.43
11 Megaselia affinis(Wood) unknown — — — 1 — — — 1 0.43
12 Megaselia brevicostalis(Wood) saprophagous 2 — 1 7 — — — 10 4.35
13 Megaselia campestris(Wood) unknown — — — 2 — — — 2 0.87
14 Megaselia ciliata (Zetterstedt) zoophagous — — — 1 — — — 1 0.43
15 Megaselia diverse (Wood) ?saprophagous — — — — — 1 — 1 0.43
16 Megaselia emarginata (Wood) unknown — — — 1 — — — 1 0.43
17 Megaselia errata (Wood) saprophagous — — 1 — — — — 1 0.43
18 Megaseliagiraudii(Egger) polyphagous — 3 — 2 — — — 5 2.17
19 Megaselia hirticrus(Schmitz) ?saprophagous — — 1 — — — — 1 0.43
20 Megaselia hortensis(Wood) ?saprophagous — — — 1 — — — 1 0.43
21 Megaselia humeralis(Zetterstedt) unknown — — — — — 1 — 1 0.43
22 Megaselia ignobilis (Schmitz) unknown — 7 11 1 6 — — 25 10.87
23 Megaselia involuta (Wood) unknown — — 2 — — — — 2 0.87
24 Megaselia manicata (Wood) ?saprophagous — 1 — — 1 — — 2 0.87
25 Megaseliapleura/is(Wood) saprophagous — — — — — 1 — 1 0.43
26 Megaseliapulicaria complex polyphagous 4 3 — 9 2 2 — 20 8.70
(Fallen)
27 Megaseliapumila (Meigen) unknown — — 1 — 1 — — 2 0.87
28 Megaselia ruflcornis(Meigen) necrophagous — — 1 1 — — — 2 0.87
29 Megaselia subnudipennis(Schmitz) necrophagous — 9 25 9 10 — — 53 23.04
30 Megaselia verralli(Wood) unknown — — — 2 — — — 2 0.87
31 Megaseliasp. (females) X 3 8 16 19 17 7 — 70 30.43
32 Phoraan‘ifronsSchmitz unknown — — — 1 — — — 1 0.43
33 Phoraatra (Meigen) saprophagous — — — 1 — — — 1 0.43
34 PhoraedentataSchmitz unknown — — — 1 — — — 1 0.43
35 PhoraholosericeaSchmitz zoophagous — — 1 — — — — 1 0.43
36 Pseudacteonformicarum(Verrall) zoophagous — — — 1 — — — 1 0.43
37 Spiniphorabergenstamni(Mik) necrophagous — — 1 — — — — 1 0.43
38 Spiniphora dorsalis(Becker) ?saprophagous — — — 1 — — — 1 0.43
39 Triphleba dudai(Schmitz) saprophagous — — — 1 — — — 1 0.43
*40 Xenotriphleba dentistylata Buck ?saprophagous — 1 — — — — — 1 0.43
Total 9 32 63 72 39 15 0 230 100.00
3.2.Phenology 2). The first individuals of Megasell'a sub—
nudipennis(23% ofthetotalcatch) andM. igno—
During the study, the highestnumber ofspecies bz'lz's (10.9%) were recorded in May. The abun-
andspecimenswereobservedinJulyandalso in dancepeaksofthesetwospeciesoccuredinJune.
June,andthelowestnumberinAprilandSeptem- M. pulicaria — complex (8.7%) and M. brevi—
ber. In October no phorids were collected (Fig. costall's (4.4%) had their abundance peaks in
1621 Durskaata]. 0 ENTOMOL. FENNICAVol. 16
40 —
35 fl 1 UI-Megaseliasubnudzpennis
w m.2-Megaseliaignobilis
30 - D3-Megaseliapolicaria
\a2“ 25 - UU45--MBoergoapslzeaiigaabsruebvsicuoltsatnaslis
g 20 M U6—-Megaseliagiraudii
g “in U7~Coniceradauci
m 15 3 U8_,Megasclr’acampestris
10 -» UU910..~MMeigaasseelialiainmvoalnuitcaata F.ig 1IThedomi.nance
5 ~ 8 9 m 11 12 n11*Megasemmmfla structureofthephond
CGanunitieSinsaline
0 l i 5 l 1‘ U12-Mcgaseliamficornis
species(males.abundance21%) D13 "Megaselia””th habitatSOftheGun:(3f
U14-others GdafiSk.
60 W W
50 “m
40 "m
30 .. {W.....«-. *M. ‘t
N‘
20 .. Fig.2. Seasonal
. 1 changesinthenumber
to -.. ofphenolspecies(3)
0 t i l l ‘i? ...,l...‘“e aanbdunrdealanticvee(pnh)oinridsaline
VI VII VIII IX X habitatsoftheGulfof
months GdafiSk.
July. Their first individuals were collected in 64%). but in Gdynia—WzgorzeM ignobilis (ca.
April. 21%) dominated. ln Gdansk—Germ Wschodnie
The phenology ofthese four most common nophoridswerecollected.
Megaselia species were characterised by one Thesaprophagousandnecrophagousphorids
abundancepeakduringthesummer(Junemluly). (over50%)werethemostabundantgroupofspe—
cieswithknownlarvaldiets.(Fig.4).Theirabun—
dancepeaksfellintheSimmer(JunemJuly)when
3.3. Species richness and abundance, most organic matter (mostly algae and fishes)
andtrophicgroups waswashedashore(Table 1).
Four Megaselia species M diver/ca, M
The highest number ofphorid species were re— lair/“times. M. pleuralz’s and M. pumila were re—
corded on beaches situated near Gdyniam cordedonthemeadows andswamps ofthe Gulf
Wagorze(over56%ofthespeciesrecorded) and ofPuck (salinity ca 7.4%). These species were
Wladyslawowo (over35% ofspecies) (Fig. 3). notobservedintheotherinvestigatedhabitats.
Thehighestabundanceofscuttleflieswasre—
cordedforthebeachesinGdynia—Wzgorze(over
42% of the total numbers of specimens) and 4. Iiscussion
GdanskmBrzeézno (over29%) (Fig. 3). The latter
locality is a typical sandy beach, with dunes. In Szadziewski (1983) during his investigation. of
Gdafisk—Brzefino, the most numerous species saline flies in differenthabitats ofPoland found
wasnecrophagousMegaseliasubnudipemis(ca. infrequentphoridspecies:Acm’gmatiasZubbockii
ENTOMOL. FENNlCAVol. lo ° Scuttleflieson the Gil/(ZfOdeaI/lSk
60
50 -_
40 —- ’9‘.‘
a? m
30 ~~ Q“
20 ‘k
Fi.g. 3. Compari.sonof to - . 10
thenumberofspecies 0 m
(S)andabundance(n)
60 will“ at, $0 “12% (I $0 $0
ofPhoridaeinsaline {a 99“ m“? 04g? 451? s9 09C) $9
habitatsoftheGulfof ‘2’ \9 “9 ,s
Gdansk. «sf
40 ~-
9..
30 ~ W .
0‘ x
as: ‘. . ‘.
‘
:20 ~~ “..
W.
N‘
Fi.g.4. Compari.sonof 10 -~ r
thenumberofspecies
(8)andabundance(n) 9
ofPhoridaeofdifferent 0gp 0‘)?» (,5; 00s a" 095:.»
trophicgroupsinsaline st? ’29 a» s9 s9 s9
st 9*“ «$1 é“ <5“ as
habi.tatsoftheGulfof $9 (£9 $9 at) $09
Gdansk. " ”if” “‘4‘
(Verrall), Megaselia brevicosralis (Wood), M foundthetrulyhalophilicspecies.Allofthespe-
minute (Aldrich), M ptrmila (Meigen), M stig~ cies found. in saline areas are known to occupy
matica (Schmitz), M. unguicularis (Wood), otherhabitats, andthe most ofthem are consid-
Pseudacteonfor/’mz’camm (Verrall) andP. [and-- ered as members ofthe soil—borne insect fauna
heater” Schmitz. Szadziewski (1983) caught no (Buck 1994-, Weber & Schiegg 2001). Saprou
phoridsin.marinehabitats. However, inbrackish phagous andnecrophagous species dominate es"
areaofthecoastaltype,Szadziewskicollectedsix peciallyopensitessuchasopenwoodlands(pine
of the above-mentioned species: in Gdansk—— plantations) and. agricultural habitats (Prescher
Gorki Wschodnie, he collected M pumz’ia, M 1992, Disney 1994, Buck 1997, Durska 2001,
stigmatica, M. unguicularis, P.formicarzrm and 2002)
P. inndbecki, and.M brevicostalisonthelocality inthe costal brackish.habitats nearPuck, we
adjacent to the GulfofPuck. in our study, only caughtonly1lphorid.individuals(M.diverse,M.
three of these species were found, viz. M hirticms,Mpleuralis,Mpumflaand.Megaselia
brevicosralis andP.formicartrm onthe beaches, spp. females). Ofthese,M. diverse andM.pleu—
butMpumila was foundnearthe GulfofPuck. ralishavepreviouslybeenrecordedbyCorbet&
Thelack.ofphoridsinGdan_skaork_iWschodnie Disney (1998) among Dipteratrapped inthe oil
wasrelatedtothefewsamplescaughtonthis 1.0-- oozingfromadeadwhale.
cality. The scuttle flies with saprophagous and/or
Neither the authors nor Szadziewski (1983) necrophagous larvae, reported from saline habi—
164 Durska etal. ' ENTOMOL. FENNICAVol. 16
tats, belong to the most abundanttrophic group. Buck, M. 1997: A new genus and species ofPhoridae
However,phoridfaunaismorenumerousinother (Diptera)fromCentralEuropewithremarkablyprimi-
maritime habitats. The beaches adjacent to the tivemaleganitalia.7Ent. Scand.28: 3517359.
Cheng,L.&Hogue,C.L. 1974:Newdistributionandhabi—
Gulf of Gdansk are rather polluted and have tatrecordsofbitingmidgesandmangrovefliesfrom
abundant organic matter, such as decaying ani- thecoastsofsouthernBajaCalifornia, Mexico (Dip—
malsandwashed-ashorealgae,thatattractsapro- tera: Ceratopogonidae, Culicidae, Chironomidae and
phagous flies. Phoridae).7Ent.News85: 2117218.
In another study, among 51 families ofDip- Corbet, S.A.&Disney,R.H.L. 1998:Dipteratrappedin
teraofsalinehabitats ofthe GulfofGdansk, the theoiloozingfromadeadwhale. 7Entomologist’s
Mon.Mag. 134: 344.
abundance ofthe scuttle flies madeup 0.75% of
Disney,R.H.L. 1990:Somemythsandtherealityofscuttle
thetotalcatch(14 samplingpositions; E. Kaczo-
flybiology.7Antenna 14: 64767.
rowska, unpubl. data). The most abundant taxa Disney, R. H. L. 1994: Scuttle flies: The Phoridae. 7
were Chironomidae (ca. 28%), Ephydridae (ca. Chapman&Hall,London. 467pp.
20%) and Chloropidae (ca. 14%). Phorids, with Disney,R. H.L.2002:Anewspeciesofmaritimescuttle
the majority being saprophagous and necro- fly (Dipt., Phoridae) from East Sussex, England. 7
phagous species, peakedinJuly, whentheyrep- Entomologist’sMon.Mag. 138: 19722.
Durska, E. 2001: Secondary succession of scuttle fly
resentedalmost30% oftheDiptera.
(Diptera: Phoridae) communitiesinmoistpineforest
inBialowieZaForest.7Fragm.Faun.44: 817130
Acknowledgements. We thank DrMatthias Buck forhis
Durska, E. 2002: The phenology ofdominant scuttle-fly
commentsonearlierversionofthemanuscript.
(Diptera: Phoridae)speciesintheBialowiezaForest.
7Entomol. Fennica13: 123—127.
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