Feeding habits of Perlodidae (Plecoptera) in the hyporheic habitats of Alpine streams (Trentino-NE Italy)

2008·0.22 MB·

by  Luana Silveri

©EntomologicaFennica.11December2008
Feeding habits of Perlodidae (Plecoptera)
in the hyporheic habitats of Alpine streams (Trentino-NE Italy)
LuanaSilveri,JoséM.TiernodeFigueroa&BrunoMaiolini
Silveri, L., Tierno de Figueroa, J. M. & Maiolini, B. 2008: Feeding habits of
Perlodidae(Plecoptera)inthehyporheichabitatsofAlpinestreams(Trentino-
NEItaly).—Entomol.Fennica19:176–183.
Toltalof75nymphsofDictyogenusfontium,PerlodesintricatusandIsoperla
(cf)rivulorumand22juvenilePerlodinaewerecollectedinhyporheichabitatsof
theNoceBiancowatershed(Trentino,NEItaly).Theidentificationoftheirlife
stagesallowedconsiderationsregardingtheirpresenceinthehyporheos,mainly
usedasarefugehabitat,particularlyduringvulnerablephasesoftheirlifecycle
(neanidstageandpre-imaginalphase).Thisfunctionispossible,giventhemore
stableenvironmentalconditionsandtheminorpredatorypressuresinthishabitat.
Thegutcontentanalysesofthethreespeciesassignedthemtotheengulfers-car-
nivorousfunctionalfeedinggroup, withslightresourcepartitionsbetweenthe
twolargestspecies.P.intricatusappearstofeedonlessmobileandfleshypreys
whileD.fontiumprefersmoresclerotizedandactivepreys.Theresultsindicate
thatthehyporheosactsnotonlyasarefugeareabutalsoasatrophichabitatfor
somePerlodidaespecies.
L.Silveri,E.MachFoundation,Dept.ofValorizationofNaturalResources,via
E. Mach 1, 30100 S. Michele all’Adige (Trento), Italy; E-mail: luana.silveri
@iasma.it
B.Maiolini,SectionofInvertebrateZoologyandHydrobiology,MuseoTriden-
tino di Scienze Naturali, Via Calepina 14, I-38100 Trento, Italy; E-mail:
[email protected]
J. M. Tierno de Figueroa, Departamento de Biología Animal, Facultad de
Ciencias,UniversidaddeGranada,18071,Granada,Spain;E-mail:jmtdef@
ugr.es
Received7August2007,accepted18October2007
1.Introduction component of the stream (Fisher 1997). In fact
streamscanbeviewedasperfusingthelandand
The vertical expansion of the spatial limits of existing‘whereverwaterflowsoverorunderthe
riverecosystems,toincludesubsurfacezones,is landscape’.Thisexpandingviewofloticsystems
crucialforabetterunderstandingoftheirecologi- has emerged from several studies which show
calfunctioning(Jones&Holmes1996). thatstreamscontinuouslyexchangewater,nutri-
Thehyporheiczone,i.e.thesaturatedintersti- ents,organicmatter,andorganismswiththeun-
tialareasbeneaththestreambedandinthestream derlying ground water (Williams 1984, Ward
banks that contain some proportion of channel 1989,Harvey&Bencala1993,Wardetal.1998).
water(White1993),isrecognisedasanintegral Thusthehyporheiczonehasbecomeasubjectof
ENTOMOL.FENNICAVol.19 (cid:127) FeedingofPerlodidaeinhyporheichabitat 177
Fig.1.Mapofthestudy
areaintheStelvioNatio-
nalPark(Trentino,N-E
Italy).
generalinterestwhenlimnologistsrecognizethat genus,twoofPerlodesandsevenofIsoperla.Itis
exchange processes between surface water and usuallyacceptedthatPerlodidaenymphsarecar-
ground water are key determinants of the river nivorous,althoughsomeofthemcaneatvegetal
structureandfunction.Suchprocessesarealsoan matterduringtheirfirstnymphalinstars(Hynes
important element for the maintenance of high 1976,Tachetetal.2000,Monakov2003).
levelsofdiversity inmacroinvertebratecenosis, Studies regarding carnivorous species allow
especially in high altitude streams. The impor- investigationofthefeedingnetsthatregulatethe
tance of surface–subsurface exchanges on eco- structure of stream communities (Allan 1995).
systemprocessesandbiodiversityinstreamshas Moreover,aninterestingresearchfieldisthere-
been addressed recently in several papers source partition among the predaceous stonefly
(Boultonetal.1998,Puschetal.1998,Dole-Oli- species (Sheldon 1980, Peckarsky 1984, Elliott
vier 1998, Bencala 2000, Jones & Mulholland 2003,Boetal.2007).Inthelastyearsthestudyof
2000,Malardetal.2000,Burgherr2000). thefeedinghabitsofcarnivorousPlecopterahas
Ingeneral,stoneflycommunitiesarenotvery been implemented particularly in Northern Ital-
diversifiedinAlpinestreams,inresponsetothe ianstreams(Bo&Fenoglio2005,Boetal.2007,
harshenvironmentalconditionsthere(Brittainet Fenoglioetal.2005,2007a,2007b,Maiolini&
al. 2000, Ward 1994). However, the hyporheic Silveri2005).Thisinterestisduetoboththeim-
stonefly communities in high altitude streams portant role of top down control of predatory
maintainaverygoodlevelofdiversityinrelation stonefliesonthemacroinvertebrateassemblages
tothecorrespondingbenthicones(Malardetal. and their role as bioindicators of environmental
2002). This is probably due to the use of the changes,becauseoftheirtoppositioninthefood
hyporheos as a refuge from the adverse condi- chain. Despite this, only few studies have dealt
tionsinsurfacewater,asnursery,andasfeeding withthefeedinghabitsofpredatoryspeciesinthe
area as suggested by Varricchione (1999) and hyporheic habitats, especially in high altitude
Boulton(2000). streams.
ElevenspeciesofPerlodidaestoneflieshave Theaimofthisworkis(i)tostudywhichspe-
been cited in Italian Alpine streams (Fochetti cies of predatory stoneflies are present in the
2004,TiernodeFigueroa&Fochetti2001,Knis- hyporheiczoneofhighaltitudestreams,(ii)tode-
peletal.2002):twospeciesofthegenusDictyo- finetheage-classcompositionofPerlodidaeliv-
178 Silverietel. (cid:127) ENTOMOL.FENNICAVol.19
Table1.Characteristicsofthesamplingsites.
Station Altitude(ma.s.l.) Typology Substrate Stream
NB3 2,270 Glacial Pebble-gravel NoceBiancoStream
NB3bis 2,270 Rhithral Cobble LarcherStream
NB4 2,260 Glacio-rhithral Cobble-gravel Confluence
inginthishabitat,asindicatoroftheroleofthe
hyporheiczoneforeachspecies,(iii)toanalyze
feeding habits of hyporheic Perlodidae and the
possibleexistenceofresourcepartition.
2.Materialandmethods
ThesamplingstationsarelocatedontheNoceBi-
anco (3rd order stream), a main tributary of the
Adige River (the second longest Italian river).
TheNoceBiancowatershedisinDelaMareVal-
ley (Stelvio National Park, Trentino, NE Italy,
46°N,10°E).Thethreesamplingsitesarelocated
Fig.2.NumberofindividualsofPerlodidaespecies
intheVeneziasubvalley(Fig.1)andtheircharac-
foundinthehyporheichabitat.
teristicsarepresentedinTable1.
Macroinvertebrateswerecollectedseasonally
(2003–2005) with various sampling methods: a
Bou-Rouchpumpinsertedintotheriverbedtoa
depth of 40 cm; bottle traps inserted in the head length vs. head width, N= 67; for I. (cf)
riverbed substratum to a depth of 30 cm, and rivulorum:Spearmanr=0.79forbodylengthvs.
hyporheicartificialsubstratesinsertedinthesedi- headlength;Spearmanr=0.81forbodylength
menttoadepthof15cm. vs.headwidth;Spearmanr=0.91forheadlength
Sampleswerepreservedin75%ethanolorin vs. head width N=7 and for P. intricatus:
4%formalininthefieldandtransportedtolabo- Spearman r = 0.97 for body length vs. head
ratory,wherenymphswereidentifiedtothespe- length; Spearman r = 0.96 for body length vs.
cieslevel.Foreachofthethreestudiedspecies, headwidth;Spearmanr=0.85forheadlengthvs.
Perlodes intricatus (Pictet, 1841), Dictyogenus head width N=89; all with P< 0.05). Thus, we
fontium (Ris, 1896) and Isoperla rivulorum choosetouseonlyheadwidthtodefinefivesize
(Pictet,1842),weusedmeasurementsfromspec- rangesfor eachspecies. Wealsoconsideredthe
imenscollectedinthehyporheosandfromindi- sizeofthewingpadsandthewingdevelopment
vidualscapturedinthebenthiclayer(fromacom- leveltodefinetheseclasses,correspondingtodif-
plementary study in the same area). Thus, we ferentstagesofnymphaldevelopmentasfollows:
choose a more complete information regarding I class (newly-emerged neanids), II class
the real size range for each species. Measure- (neanids),IIIclass(neanidswithtracesofwing
ments of body length (fromthe head to the last pads), IV class (nymphs with well-developed
urite) and head dimension (length and width) wing pads) and V class (nymphs ready to
were taken with an ocular micrometer micro- emerge).
scope.Allthreemeasureswerehighlycorrelated Toanalyzethefeedinghabitsofthedifferent
(for D. fontium: Spearman r = 0.79 for body Perlodidae nymphs, we extracted their gut con-
length vs. head length; Spearman r = 0.82 for tents. Preys were identified using undigested
bodylengthvs.headwidth;Spearmanr=0.92for chitinouseparts,especiallyheadcapsules.
ENTOMOL.FENNICAVol.19 (cid:127) FeedingofPerlodidaeinhyporheichabitat 179
3.Resultsanddiscussion
3.1.Speciesfoundinthehyporheiczone
Onlythreespecies,D.fontium,P.intricatusandI.
(cf)rivulorum,oftheelevenPerlodidaeknownin
theItalianAlps(Fochetti2004,TiernodeFigu-
eroa&Fochetti2001,Knispeletal.2002)were
identifiedinthehyporheiczoneofoursampling
stations (Fig. 2). This scarce biodiversity was
probablyduetothesevereenvironmentalcondi-
tionsofhighelevationfreshwaterecosystems.
D.fontiumiswidespreadintheItalianAlps,
whereitpopulates rhithralstreams even athigh
Fig.3.Distributionofthefivesizeclassesofthe
elevations.InTrentinoithasbeenrecordedupto
nymphsofthreespecies.
2700 m.a.s.l. (Lencioni et al. 2002). Adults
emerge from June to September (Consiglio
1980). shown.
P.intricatusisanotherpredatoryspeciespres- Although we found a low number of speci-
entintheTrentinoAlpsthatcanbeclassifiedas mensofD.fontiumandI.(cf)rivulorum,ourre-
an orophile species of fast flowing waters sults suggest that these species do not use the
(Consiglio1979)andinhabitingthehyporhithral hyporheic habitat during the intermediate sta-
and rhithral zones (Consiglio 1980). The adults diumoftheirdevelopmentbutonlyduringtheir
presentasummerflightperiod,fromJunetoJuly last nymphal instars (Fig. 3). Probably the
(Consiglio1980). hyporheosactsasarefugeareawherethenymphs
I.rivulorumisanorophilespeciesdistributed cancompletetheirdevelopmentandgrowth.
mainlyinCentralEurope.Itlivesinrhithralhabi- P.intricatusisthemostabundantPerlodidae
tatsanditsflightperiodextendsfromJunetoSep- foundinoursamplingarea(Fig.2).Ourresults
tember(Consiglio1980). highlightthatthisspeciesusesthehyporheiczone
OnlyoneotherspeciesbelongingtoPerloidea mainlyduringthecentralandthefinalphasesof
superfamily was found in the same habitat: itslifecycle(Fig.3).However,somefirstinstarP.
Chloroperla susemicheli Zwick, 1967 (family intricatusnymphsalsoseemtousethehyporheic
Chloroperlidae)(Silverietal.2007).Thisisthe habitat(Fig.3).
most abundant predatory stonefly species col- The presence of some juvenile Perlodidae
lected in the hyporheic habitat of our stations (Fig.2)togetherwiththepresenceoffirstinstar
(49%). The three species of Perlodidae, plus nymphsofP.intricatus,suggestthenurseryrole
somenon-identifiedjuvenilePerlodidaenymphs, ofhyporheichabitat.
constitutetogethertheremaining51%. Theseresultssupporttheideathattheuseof
NoPerlidaespecieswerefound,butthisfact thehyporheosisanimportantrefugehabitatfor
couldberelatedtothetotalabsenceofPerlidaein some amphibiotic stonefly species (Williams
the benthos of high altitude streams (over 1800 1984,Varrichione1999,Boulton2000,Bencala
m.a.s.l.)ofTrentino(Fochetti2004). 2000), especially during the most vulnerable
phasesoftheirlifecycle.Thisimportantfunction
is due to the more stable environmental condi-
3.2.Relationshipbetweennymphalsize tions and the minor predator pressure in the
anduseofhyporheosasahabitat hyporheic zone, especially in high altitude
streams.So,thehyporheicbufferseemstobean
In Figure 3, the Perlodidae species collected in ideal area to spend the most sensitive nymphal
thehyporheichabitatandtheirclassificationac- stages(neanidstageandpre-imaginalphase)for
cording to the five developmental stages are thesePerlodidaespecies.Onthecontrary,itap-
180 Silverietel. (cid:127) ENTOMOL.FENNICAVol.19
Fig.4.Percentageof
itemsfoundinthegut
contentsofthethree
studiedPerlodidae
species.
pearsthat,inthesamearea,C.susemichelispends Ofthe56studiedP.intricatus,52hadgutcon-
allitslifecycleinthehyporheicareasuggesting tents(Table3).ThisspeciesfeedsmainlyonChi-
thatitisatypicalhyporheicspecies(Silverietal. ronomidlarvae,butalsoonPlecoptera(probably
2007). belongingtoPerlodidae,LeuctridaeandNemou-
ridae), other Dipterans (Limoniidae and Simu-
liidae) and Trichoptera. Large quantities of di-
3.3.Feedinghabits gested chitinous parts were found inside their
guts,buttheiridentificationwasnotpossible.De-
The gut contents of the three analyzed stonefly tritus and vegetal matter were also found in a
species are shown in Figure 4 and Tables 2, 3 largequantity.Pintricatusisalsoalargepredator
and4. species(maturenymphscangrowfrom15to25
SevenoftheeightstudiedD.fontiumhadgut mmlong,accordingtoConsiglio,1980).Biologi-
contents (Table 2). Our results seem to suggest cal data of this species are scarce compared to
preferenceforpreyingonotherstoneflyspecies those of other species of the genus, such as
(probablybelongingtoNemouridaeandPerlodi- Perlodes microcephalus (Pictet, 1933), which
dae),despitetheyarenotthemostcommonprey feeds also mainly on Chironomidae and other
inthehyporheosofhighaltitudestreams(Milner aquatic macroinvertebrates in benthic Pyrenean
& Petts 1994, Maiolini & Lencioni 2000), and populations(Berthélemy&Lahoud1981).
vegetable matter. Moreover, they also prey on AllsevenanalyzedindividualsofI.(cf)rivu-
Chironomidlarvae(themostabundantpreyinthe lorum had gut contents but four were severely
hyporheos)andotherunidentifiedinsects(may- damagedandthusgutanalyseswerenotpossible
fliesorstoneflies). (Table4).Thisspeciesappearstofeedmainlyon
D. fontium is one of the largest predatory Chironomidae larvae. Vegetable and detritus
stonefly present in Alpine streams (mature matter were also frequent in the gut. There was
nymphsreachlengthsfrom15to25mm,accord- also one Collembola specimen among the prey,
ingtoConsiglio,1980),andtheirfeedinghabits probably ingested incidentally. This species is
havebeenpreviouslystudiedinbenthicpopula- considerablysmallerthantheotherstudiedPerlo-
tions,showingsomedifferencesbetweenlocali- didae (mature nymphs grow from10 to 12 mm
ties.Thus,inastudyinTrentino,nymphsshowed long,accordingtoConsiglio,1980).Thereareno
an opportunistic character preying on the more dataonfeedinghabitsofthisspeciesinItaly,butit
numerous taxa in the community (Maiolini & is usually considered that Isoperla species, at
Silveri 2005), while in a study in Piemonte, least in the benthos, are mainly predators, al-
Fenoglioetal.(2007b)reportedapreferencefor thoughsomespeciesfeedentirelyonvegetation
Chironomidaeandthepresenceofvegetaldetri- (Hynes1976).
tusandalgaeinthepreimaginaldiet. Thepresenceofvegetalmatteranddetritusin
ENTOMOL.FENNICAVol.19 (cid:127) FeedingofPerlodidaeinhyporheichabitat 181
Table2.GutcontentofD.fontium(N=8).
Items Mean Min–Max SD Presence
Chironomidae 0.25 0.00–1.00 0.46 2(25%)
Plecoptera 0.50 0.00–1.00 0.53 4(50%)
Unid.prey 0.25 0.00–1.00 0.46 2(25%)
Veg.Mat.(%) 12.50 0.00–60.00 23.75 2(25%)
Table3.GutcontentofP.intricatus(N=56).
Items Mean Min–Max SD Presence
Simuliidae 0.04 0–1 0.19 2(3.6%)
Limoniidae 0.12 0–2 0.38 6(10.7%)
Chironomidae 4.36 0–35 6.92 36(64.3%)
OtherDiptera 0.02 0–1 0.13 1(1.8%)
Trichoptera 0.05 0–1 0.23 3(5.4%)
Plecoptera 0.46 0–4 0.87 18(32.1%)
Unid.prey 0.20 0–1 0.40 11(19.6%)
Detritus(%) 11.96 0–100 25.68 16(28.6%)
Veg.Mat.(%) 2.41 0–65 9.53 6(10.7%)
Table4.GutcontentofI.(cf)rivulorum(N=7).
Items Mean Min–Max SD Presence
Chironomidae 2.00 0–4 1.41 6(85.7%)
Plecoptera 0.29 0–2 0.76 1(14.3%)
Collembola 0.14 0–1 0.38 1(14.3%)
Unid.prey 0.14 0–1 0.38 1(14.3%)
Detritus(%) 13.75 0–6 24.27 2(28.6%)
Veg.mat.(%) 2.86 0–20 7.56 1(14.3%)
high quantities in the guts of these predaceous Britain (Elliott 2000). The sharing of food re-
stoneflyspeciescouldberelatedtotheirfeeding sourcesamongcoexistingPerlodidaespecieshas
mechanism. In fact, they can be classified as been previously demonstrated in benthos (e.g.
engulfers-carnivoroussensuCummins&Merritt Sheldon1972).Ourresultssuggestthatthehypo-
(1996) and, as pointed out by Hynes (1976), in rheoscouldactnotonlyasarefugeareabutalso
the carnivorous stoneflies food is very often asanimportantfoodresourceforsomePerlodi-
accompainedbyalgaeanddetritus. daespecies.
Despitethelownumbersofindividualsoftwo From a more general point of view, and re-
ofthestudiedspecies,theresultsindicateaslight gardingallthestoneflycommunitypresentinthe
resourcepartitionatleastbetweenthetwolargest studiedhyporrheicarea,Perlodidaespeciesshare
species.Thus,P.intricatusseemstofeedonless theirroleaspredatorswiththeChloroperlidspe-
mobileandfleshypreys(suchasChironomidae, ciesC.susemicheli(considerablysmaller,8mm,
Limoniidae,Simuliidae.)whileD.fontiumfeeds accordingtoFochetti,2004),whichspendsallits
mainly on more sclerotized and active preys lifecycleinthishabitatandfeedsmainlyonthe
(such as other Plecoptera). The preference of most common preys (Chironomidae) and more
Perlodes(atleastP.microcephalus)forsedentary scarcelyonothermoreactivepreys(Silverietal.
preyshasalsobeenpointedoutinaworkinGreat 2007).
182 Silverietel. (cid:127) ENTOMOL.FENNICAVol.19
References dae)inanApenninefirstorderstream(RioBerga,NW
Italy).—Ann.Soc.Entomol.Fr.43(2):221–224.
Fenoglio,S.,Bo,T.&Malacarne,G.2007b:Preimaginal
Allan,J.D.1995:Streamecology.Structureandfunction
feeding habits of Dictyogenus fontium (Plecoptera,
ofrunningwaters.ChapmanandHall,London,388p.
Perlodidae)inanalpinebrookinNWItaly.—Ento-
Bencala,K.E.2000:Hyporheiczonehydrologicalproces-
mol.Fenn.18:27–31.
ses.—Hydrol.Process14:2797–2798.
Fisher, S. G. 1997: Creativity, idea generation, and the
Berthelemy,C.&Lahoud,M.1981:Regimesalimentaires
functionalmorphologyofstreams.—J.N.Am.Be-
etpiecesbuccalesdequelquesPerlodidaeetPerlidae
nhtol.Soc.16:305–318.
desPyrenées(Plecoptera).—Ann.Limnol.17(1):1–
Fochetti,R.2004:Plecoptera.—InRuffo,S.&Stoch,F.
24.
(eds.),ChecklisteDistribuzionedellaFaunaItaliana.
Bo,T.&Fenoglio,S.2005:Age-relatedshiftinthedietof
Ministerodell’AmbienteedellaTuteladelTerritorio.
Perla marginata in a woodland Apenninic creek of
Direzione per la Protezione della Natura. CKmap
NWItaly(Plecoptera:Perlidae).—Entomol.Gener.
2004–versione5.1:143–147.
28(2):147–154.
Harvey,J.W.&Bencala,K.E.1993:Theeffectofstream-
Bo,T.,Fenoglio,S.&Malacarne,G.2007:DietofDino-
bedtopographyonsurface-subsurfacewaterexchange
crascephalotesandPerlamarginata(Plecoptera,Per-
inmountaincatchments.—WaterRes.29:89–98.
lidae)inanApenninestream(northwesternItaly).—
Hynes,H.B.N.1976:BiologyofPlecoptera.—Ann.Rev.
Can.Entomol.139(3):358–364.
Ent.21:135–153.
Boulton,A.J.2000:Thefunctionalroleofthehyporheos.
Jones,J.B.&Holmes,R.M.1996:Surface–subsurface
—Verh.Int.Ver.Limnol.27:51–63.
Interactions in stream ecosystems. — Trends Ecol.
Boulton,A.J.,Findlay,S.,Marmonier,P.,Stanley,E.H.&
Evol.11:239–242.
Valett,H.M.1998:Thefunctionalsignificanceofthe
Jones,J.B.&Mulholland,P.J.2000:StreamsandGround
hyporheiczoneinstreamsandrivers.—Ann.Rev.
Waters.AcademicPress,SanDiego,425pp.
Ecol.Syst.29:59–81.
Knispel, S., Rosciszewska, E., Vinçon, G. &Lubini, V.
Brittain,J.E.,Adalsteinsson,H.,Castella,E.,Gislason,G.
2002:ThestatusofPerlodesjurassicusAubert,1946
M.,Lencioni,V.,Lods-Crozet,B.,MaioliniM.,Mil-
(Insecta: Plecoptera: Perlodidae). — Mitt. Schweiz.
nerA.M.&SaltveitS.J.2000:Towardsaconceptual
Entomol.Ges.75:183–189.
understandingofarcticandalpinestreams.—Verh.
Lencioni,V.,Boscaini,A.,Franceschini,A.,Maiolini,B.
Int.Ver.Limnol.27(2):740–743.
2002: Distribution of benthic invertebrates in high
Burgherr,P.2000:Spatio-temporalCommunityPatternsof
mountainstreamsintheItalianAlps:areviewandre-
LoticZoobenthosAcrossHabitatGradientsinanAl-
centfinding.—AttidelXIIConvegnoSoc.Ital.Ecol.
pineGlacialStreamEcosystem.PhDThesis,Zurich,
(S.It.E), Sabaudia (LT), 2001 Atti S.It.E., 25 (CD-
Switzerland.
ROM)
Consiglio,C.1979:LadistribuzionedeiPlecotteriitaliani.
Maiolini,B.&Lencioni,V.2000:Aglacialstreamecosys-
Estr.Soc.Ital.—Biogeografia6:383–393.
tem in the Italian Alps. — Verh. Internat. Verein.
Consiglio,C.1980:Plecotteri(Plecoptera).—Guideper
Limnol.27(2):716–719.
il riconoscimento delle specie animali delle acque
Maiolini,B.&Silveri,L.2005:FeedinghabitsofDictyo-
interneitaliane.9,68p.
genus fontium (Plecoptera Perlodidae) in Alpine
Cummins,K.W.&MerrittR.W.1996:Ecologyanddistri-
streams(Trentino-NEItaly).—StudiTrent.Sci.Nat.
butionofaquaticinsects.–In:Merritt,R.W.&Cum-
ActaBiol.82:77–83.
mins,K.W.(eds),Anintroductiontotheaquaticin-
sectsofNorthAmerica:74–86.Kendall&Hunt,Du- Malard,F.,Ward,J.V.&Robinson,C.T.2000:Anex-
buque,Iowa3rdedition. pandedperspectiveofthehyporheiczone.—Verh.
Internat.Verein.Limnol.27:431–437.
Dole-Olivier, M. J. 1998:Surfacewater-grondwaterex-
changeinthreedimensionsofabackwateroftheRho- MalardF.,Tockner,K.,Dole-Olivier,M.J.&Ward,J.V.
neRiver.—Freshwat.Biol.40:93–109. 2002:Alandscapeperspectiveofsurface–subsurface
Elliott,J.M.2000:Contrastingdielactivityandfeeding hydrological exchanges in river corridors. —
patternsoffourspeciesofcarnivorousstoneflies.— Freshwat.Biol.47:621–640.
Ecol.Entomol.25:26–34. Milner,A.M.&Petts,G.E.1994:Glacialrivers:physical
Elliott,J.M.2003:Acomparativestudyofthefunctional habitatandecology.—Freshwat.Biol.32:295–307.
responseoffourspeciesofcarnivorousestoneflies.— Monakov,A.V.2003:Feedingoffreshwaterinvertebrates.
Freshwat.Biol.48:191–202. KenobiProductions,Belgium,371p.
Fenoglio,S.,Bo,T.&Cucco,M.2005:Winterpreyprefe- Peckarsky,B.L.1984:Predator-preyinteractionsamong
renceofPerlodesmicrocephalus(Pictet,1833)(Ple- aquaticinsects.—In:Resh,V.H.&Rosenberg,D.M.
coptera,Perlodidae)nymphsinanApenniniccreek, (eds.), The Ecology of Aquatic Insects: 196–294.
Northestern Italy. — Entomol. News. 116(4): 245– PraegerPublishers,NewYork.
252. Pusch,M.,Fiebig,D.,Brettar,I.,Eisenmann,H.,Ellis,B.
Fenoglio,S.,Bo,T.,Pessino,M.&Malacarne,G.2007a: K., Kaplan, L. A., Lock, M. A., Naegeli, M. W. &
FeedingofPerlagrandisnymphs(Plecoptera:Perli- Traunspurger,W.1998:Theroleofmicro-organisms
ENTOMOL.FENNICAVol.19 (cid:127) FeedingofPerlodidaeinhyporheichabitat 183
intheecologicalconnectivityofrunningwaters.— Varricchione,J.T.1999:Verticalandseasonaldistribution
Freshwat.Biol.40:453–495. ofhyporheicinvertebratecommunitiesinseveralIda-
Sheldon,A.L.1972:ComparativeecologyofArcynopte- hoandMontanastreams.M.Sc.Thesis,IdahoState
ryxandDiurainaCaliforniastream.—Arch.Hydro- University,Pocatello,210pp.
biol.69:521–546. Ward,J.V.1989:Thefour-dimensionalnatureofloticeco-
Sheldon,A.L.1980:ResourcedivisionbyPerlidstonefli- systems.—J.N.Am.Benthol.Soc.8:2–8.
es(Plecoptera)inalakeoutletecosystem.—Hydro- Ward,J.V.1994:EcologyofAlpinestreams.—Freshwat.
biol.71:155–161. Biol.32:277–294.
Silveri,L.,TiernodeFigueroa,J.M.&Maiolini,B.2007: Ward,J.V.,Bretschko,G.,Brunke,M.,Danielopol,D.L.,
Biologíaninfaldeunaespecietípicadeplecópterodel Gibert, J., Gonser, T. & Hildrew, A. G. 1998: The
hábitat hiporreico alpino; Chloroperla susemicheli boundariesofriversystems:themetazoanperspecti-
Zwick, 1967 (Plecoptera, Chloroperlidae). — XXV ve.—Freshwat.Biol.40:531–569.
JornadasdelaAsociaciónespañoladeEntomología. White,D.S.1993:Perspectivesondefininganddelinea-
Málaga(Spain). tinghyporheiczones.—J.N.Am.Benthol.Soc.12:
Tachet,H.,Richoux,P.,Bournaud,M.&Usseglio-Polate- 61–69.
ra, P. 2000: Invertébrés d’eau douce. Systématique, Williams,D.D.1984:Thehyporheiczoneasahabitatfor
biologie,écologie.CNRSÉditions,Paris,588p. aquaticinsectsandassociatedarthropods.—In:Resh,
TiernodeFigueroa,J.M.&Fochetti,R.2001:Isoperla V. H. & Rosenberg, D. M. (eds.), The Ecology of
zwickisp.n.(Plecoptera,Perlodidae),anewItaliansto- Aquatic Insects: 430–455. Praeger Publishers, New
nefly.—Rev.Suis.Zool.,108(3),483–486. York.