GulfResearchReports, Vol. 8, No. 3, 259^270, 1991 HAUSTORIUS JAYNEAE, A NEW SPECffiS OF HAUSTOKHD AMPHIPOD FROM THE NORTHERN GULF OF MEXICO, WITH NOTES ON ITS ECOLOGY AT PANAMA CITY BEACH, FLORIDA U.S.A. JOHN M. FOSTER* AND SARA E. LECROY* ^504 East Pine ForestDrive. Lynn Haven, Florida 32444 ^Invertebrate Zoology Section, GulfCoast Research Laboratory, P.O. Box 7000. Ocean Springs, Mississippi 39564 ABSTRACT A new species of sand-burrowing ampbipod, Haustoriusjayneae, is described from the swashzoneand shallowsubtidalsandsalongthenorthFloridaandMississippiGulfcoasts. It ismostsimilar to H. canadensis from the American Atlantic coast, differing primarily in the presence of a distinct anterodistal spinous lobe on pereopod 6, article 5; a longer row of distal marginal spines on pereopod 7, article 4; and fewerproximal spines on the peduncle ofuropod 1. A revised keyto the known species of Haustorius is included andinformation ontheecology of//.jayneaen. sp. at Panama CityBeach, Florida, is reviewed. Introduction Five additional haustoriidspecies originally assigned Taxonomic and zoogeographic studies of Gulf of to the genus Haustoriushave sincebeen placedin other MexicoHaustoriidaearescarce. Alackofkeys forGulf genera. These include the Gulf of Mexico species material, a reflection of the underdeveloped stale of Pseudohaustorius americanus (Pearse, 1908) and the knowledge about the family in the region, has limited North Atlantic species Acanthohaustorius spinosus woricers to the use ofkeys and guides written primarily (Bousfield, 1962), both removed from Haustorius by forAtlanticcoastmaterial. As aresult,government and Bousfield (1965). In addition, the northem Pacific private environmental assessment reports often provide species Eohaustorius washingtonianus (Thorsteinson, species lists in which citations are limitedto genera, or 1941), E. eous (Gurjanova, 1951), and E. cheliferous where species are listed which do not occurin the Gulf (Bulycheva, 1952) were removed from Haustorius by of Mexico. Barnard (1957). Existing knowledge of the Gulf Haustoriidae is re- Anumberofundescribedhaustoriidspeciesareknown ported primarily in papers which describe new species to occur in the Gulf of Mexico. Bousfield (1970) (Pearse, 1908; Robertson and Shelton, 1978; Robertson indicated that at least ten undescribed species ofHaus- and Shelton, 1980; Thomas and Barnard, 1984; Foster, toiiidae occur in the region, although the number of 1989) and in several ecological papers which have species inthetype genus was notreported. In addition, reported undescribed species and recognized them as recent studies haveresulted inthe reporting ofa ‘Tong- such (Thomas, 1976; Shelton and Robertson, 1981). rosfrate” Haustorius species from North Carolina Foster (1989) reviewed the history ofhaustoriid studies (Bousfield, 1965; Fox and Bynum, 1975). Although no in the Gulfand listed the known species. formal description was published, this form is included Amongthenumerous taxonomicproblems associated in the keyprovided in this paper. with the Haustoriidae, questions concerning the type EcologicalreportswithreferencetoHaustoriusinthe genus Haustorius Muller, 1775 are particularly signifi- northemGulfofMexico are numerous. Forexample, in cant. Threespeciesarecurrentlyrecognizedinthegenus. the area between Cape San Bias, in the Florida Pan- The type species,Haustorius arenarius (Slabber, 1769), handle, and Mississippi Sound, the genus has been is distributed in the northeastern Atlantic and has also reported by Saloman (1976), Saloman and Naughton been reported from the Gulf of Mexico (Pearse, 1912), (1977;1978), Saloman et al. (1982), Taylor (1987), and althoughCroker(1967)consideredsuch earlyrecords to Heard and Stuck (1988). Thomas (1976) also reported betheresultoferroneousidentifications. Theremaining an undescribed species of Haustorius from Barataria two species, Haustorius canadensis Bousfield, 1962 and Bay,Louisiana, occuringinfinesandfrom thedrift line Haustorius algeriensis Mulot, 1967, are distributed in to a depth of 1 -2 meters, and Robertson and Shelton the northwestern Atlantic and along the North African (1980) found an undescribedspecies ina similarhabitat coast in the Mediterranean Sea, respectively. on the Texas coast. Manuxeript receivad Oclobar 12, 1990; accepted December 19, 1990. 259 260 Foster and LeCroy PK-f,USNM 250742, Perdido Key,Florida, swa.shzone Methods in medium sand, 23 July 1987, coll. R.W. Heard. Male, 10.0 mm, MISS-a, USNM 250743; female, 10.0 mm, MISS-b,USNM250744;female,8.0mm,MlSS-c USNM Material for liiis study came from several locations 250745,RangerLagoon,HornIsland,MississippiSound, ainlcolnugdefiSlelcAonadstrsewofBaHyo,rPiadanamanadCiMtiyssBiesasicphp,i.CapTehSeasen swa.sli zone, 25 Jan. 1989, coll. R. W. Heaid. AdditionalMaterial: 5 males,9females,4juveniles, IBsilaasn,das,ndMiPsesridsisdioppKie.y,IFnloarlildal,ocaalsitwieelsl,aasniHpohrinpoadnsdwSleiriep U11S42N,MSt2A50n7d4r6e;w4Bamya,leFsl,or8idaf,emWaelesst,Pa1sjsu,vemneidlei,umGCsaRnLd scuolclteicotneddeivllictehse s(wyaasbhbyzopnuempasn)d, fpruosmh tniedtasl,poorolscowriitnhg Finoswtearv.e4pomoalleasb,ov5efsewmaaslehs,zo7nej,uv1e4niOlcets.,1U9S89N,Mcol2l5.0J7.4M7.; tools. See Salomon (1976) and Heard and Stuck(1988) 31 males, 42 females (I ovg,), 73 juveniles, USNM for detailed iiiforinatiou on localities, methodology, 250748; 7 males, 7 females (1 ovg.), 9juvetiiles, GCRL sedinienlology, and associated fauna. 1143,PerdidoKey,Florida,subtidalsand,4-6Oct. 1989, aasnddMoparolssgatilerniasonrdo,fbvteelncitearuaaslnetieonnfnttahheeeitarenxodtr,iuearn,stoapotopidopsnosaaelrdeonrtgeofteihureirtmeedariitonor cUolSl.NRM.W2.50H7e4a9r;d.1 2mamlael,es1, f1efmeamlael.eG(oCvRg.L),121j4u4v,enHiloersn, Island, Mi$.si.ssippi Sound, swash zone sand, 25 Jan. axis ofthe body. 1990. coll. R. W. Heard. 7 males, 4 females (3 ovg.), USNM250750;8males,3 females(2ovg.),GCRL 1145, Haustoriidae Sicbbing, 1906 Ship Island, Mississippi Sound, subtidal sand, 12 July Haustoriinac Bousfield, 1965 1988, coll. R. W. Heard. 2 males, 2 females, USNM Haustorius Muller, 1775 250751; 1 male, 1 female, GCRL 1146, Ship Island, Haustorius jayneae, new species Mississippi Sound, swash zone sand, 12July 1988, coll. Figures 1-4 R.W. Heard. Haustorius new species: Saloman and Naughton, 1977, Diagnosis pp. 359-362 Antenna 1, accessory flagellum 4-5 segmented. Haustorius species: Saloman and Naughton, 1978, pp. Rostrum short, subacute, wide at base, not exceeding 67-68 midpoint ofantenna 1, peduncle 1. Pereopod 5, article 6, anterior margin with 3-4 spine groups. Pereopod 6, Material Examined article4, posteriormarginmarkedly oblique proximally, bearing 3-4 spines distally; article 5 subquadrate with Holotype: Female, 6.0mm, SAB-e, St. Andrew Bay, distinct anterodistal spinous lobe. Pereopod 7, coxal Florida, West Pass, medium sand in wave pool above plate with setae on posterodistal margin only; article 4, swash,25 °C, 28ppt, 14Oct. 1989,USNM250725,coll. proximal margin sharply set offfrom posterior margin, J. M. Foster. posterior margin with 1 spine group, distolateral mar- Paratypes: Female, 8.0 mm, SAB-a, GCRL 1141; ginal spines extending half length of distal margin. female, 5.3 mm, SAB-b, USNM 250726; male 5.0 mm, Uropod 1,peduncle, dorsolateral marginwith 1-2proxi- SAB-c, USNM 250727; male. 4.0 mm, SAB-d. USNM malspines,proximal anddistalspinesonly. Telsoncleft 250728; male,6.0mm,SAB-f,USNM250729;male,7.0 one-third distance to base. mm,SAB-g,GCRL 1141; male,5.0mm.SAB-h,USNM 250730; female,7.0mm,SAB-i, USNM250731;female, Description 7.0 mm, SAB-j, USNM 250732; male, 6,0 mm, SAB-k, USNM250733,PanamaCityBeach,Florida,moderately Paratvpe male SAB-f. 6.0 mm. Panama City Beach. sortedfinesand, swash zone, 18.0°C, 32.70 ppt,4 Feb. Florida 1975,coll.C.H.Saloman. Male,5.5mm,CSB-a,USNM 250734; male, 6.0 mm, CSB-b, USNM 250735; female Head - Broadest medially, rostrum blunt, wide at (ovg), 5.0mm, CSB-d, USNM250736; female,5.0mm, base; slightly exceeding anterolateral apices, extending CSB-f, USNM 250737; female, 7.0mm. CSB-g, USNM one-quarter of dorsally visible length of antenna 1, 250738, CapeSanBias,Florida, wet,intertidal finesand peduncle 1; antennal sinuses markedly convave. with shell hash, 27.5 °C, 29ppt, 27 Sept. 1987, coll. J. Antenna1-Pedunclearticle 1 and2subequal,article M. Foster. Male,7.5 mm,CSB-c, USNM250739; Cape 3 two-thirds length ofarticle 2; peduncle 1, dorsolateral San Bias, Florida, longshore tidal pool on moderate margin lined with plumose setae, ventrolateral margin energybeachinfinesand, 16.8°C,30ppt, 11 Mar. 1989, with4pilosespines; peduncle 2 wideneddistally,dorsal coll.J. M. Foster. Male,6.0mm.PK-d, USNM250740; margin with a row of plumose setae interspersed with female 6.0 mni, PK-e, USNM 250741; female, 7.0 mm. shortersimple setae, lateralsurface withmixedplumose A New Haustorud Ampidi^od From Tiie Golf Of Mexico 261 Figure 1, Haustoriusjayneae n. sp„ Lateral view ofadult female (6.0 mm) from St. Andrews Bay, Florida. Scale = 1.0 mm. andsimplesetae;peduncle3,ventralmarginwithrowof Lower Lip - Iimerlobes extending two-thirds length long pilose spines inserted near articulationwith flagel- ofouter lobes, truncate distally and finely pilose; outer lum; flagellum wilh 9 articles, each with short simple lobesbroadlyrounded,pilosearoundmargins,bothlobes setae inserted letiiiinally, several wilh aesihetsacs; with numerous short spines along inner distal margin. accessory flagellum 4 segmented. Mandible - Right side, incisorbifid, rakerrow of 10 Antenna 2 - Peduncle 4 expanded venlrally to form distallyserrateblades;molartriiuralivewilh 1 projecting deepJobewithbroadly roundeddistalprojection,ventral plumoseseta;palparticle 2withmarginalandfacialrow margin with 22 spines inserted laterally and a row of ofshort simple setae, article 3 with 17 pectinate spines densely plumose setae inserted medially along margin, incombrow, 14-15distallytapered,minutelypectinate 5 plumose spines on proximal half of ventral margin, tenninalspines. Leftside, laciniamobilisshort,conical. lateral surface with row of5 setae nearproximal dorsal Maxilla 1 • Inner plate wilh 10 sparsely plumose margin,medialsurfacewithobliquerowof6setaeacross marginal setae; outer plate with 4 stout, smooUi, blunt width of article, dorsal margin with distolaleral row of and 12 slender, minutely serrate, subacute distal spines; plumosesetae,ventralmarginwith2-3thinpilosespines palparticle2withmarginalandapicalplumosesetae,and distally in sinus formedby distal lobe of article; article tapered tenninal spines with recurved tips; bailer lobe 5 slightly over half length of article 4, with strongly large and densely setose. convex ventral lobe, ventral margin lined with long Maxilla 2 • Inner plate linguiform, slender, with plumosesetae,disloventralcomerwithclusterofplumes, plumose marginal setae and oblique row of plumose several thin spine-like setae and 1 Uiick pilose spine, facial setae; outerplate large,lunate, outermarginlined distolaleral margin with row ofthinner, shorter plumose with fine setae, 14 stout, distally tapered comb spines setae and scattered slender, simple setae; distal half of medially, inner margin with 30 - 32 sparsely plumose dorsal margin with row of plumose setae; flagellum of setae distally, lined with minutely plumose setae proxi- 10 articles, article 1 longest, with disloventral row of mally. plumose setae, article 2 half lengtli of article 1 and Maxilliped-Innerplatewith 11 innermarginalsetae, bearing 1 disloventral plumose seta, article 3 with 1 proximal setae short and finelypectinate on both edges, disloventralplutnoseseta,remainingarticleswithgroups distal .setae longer,plumose, apical marginwith2 blunt, of simple temiinal setae. stout spines, aboral surface wilh 2 penicillaie setae and Upper Lip Broad, apex flattened, comers abruptly a row ofdistal spines, oral surface with transverse row rounded. 262 Foster and LeCroy Figure2. Haustoriusjayneaen.sp.,paraljpemaleSAB-f(6.0 mm): (A) mandible;(B)maxilla 1; (C)maxilla2; (E)lower Up. Adult male(6.0 mm),St. Andrew Bay, Florida: (D) maxUllped. Scales: a = 0.2 mm (B-C,E); b = 0.2 mm (A); c= mm 0.4 (D). of distal spines; outer plate slightly broader than inner distal margin with a row of simple setae, increasing in with 12recurvedspines andnumerous transerve rows of lengthdistally; article 2narrowedproximallywith long, setae; palparticle 3 withexpanded distally, dense trans* widely spaced simple setae on posterior margin; article verse rows ofsetae oninner margin, article 3 geniculate 5, posterior margin with dense clusters of long simple withlongserratesetaeandsimplesetaeondistalmargin, setaealonglateralandmedialsurfaces; article6one-half 6-7 9elongate spines terminally, aboral surface with central length of article 5, anterodistal margin with row of simple setae. transverse rows of long, distally recurved, finely pecti- Coxal Plates-Plates 1-4increasinginsizewitheach nate setae, posterodistal margin with 5 row of shorter, successive plate, combined ventral margins forming a distally recurved, finely pectinate setae, posterodistal gentle curve, margin with 5 rowsofdistallyrecurved, finelypectinate Gnathopod 1 - Coxa deeper than wide, gently con- setae; article 7 one-quarterlengthofarticle 6,projecting caveposteriorlywith6plumoseposteriormarginalsetae, nail subequal in length to article 7. posterovental angle with 3 long, plumose setae, antero- A Haustoriid Amphipod From The Gulf Of Mexico 265 Gnathopod 2 - Coxa deeper than wide, anterior with several short setules proximally; article 4 with margin convex, posterior margin nearly straight, with 6 plumose setae onposteriormargin, anteriormargin with plumosesetaedistally, anterodistalmarginwith6simple 3 stoutmarginalspinesinterspersed inarow ofplumose setae; article 2slightly narrowedproximallywithrow of setae,anterodistalmarginwithaclusterof4spines,distal evenly spaceddusters oflong simple setae onposterior margin with a row of 6 spines, lateral surface with 6 margin; article 5, anterior margin with evenly spaced clustersof3-6stoutspines,medialsurfacewithclusters groups ofminutely pectinate setae, outerlateral surface of plumose setae; article 5, distomedial margin with with scattered simple setae, anterodistal margin with cluster of long plun^ose setae, posterior half of distal cluster of 5 minutely pectinate setae, posterior margin marginwitharowof6stoutspines,posterodistalmargin with 3-5 groups ofmedially inserted, spatulate comb lined with plumosesetae, anterior marginwith 1 cluster spines on distal half, row of simple setae along entire of2 spines, anterodistal angle with cluster of5 spines, margin; article 6, anterior margin with 6 - 7 transverse lateralsurfacewith4clustersof4- 10stoutspines;article rows oflong,distally recurved,minutelypectinatesetae, 6 nakedposteriorly, anterior marginwith 3 clusters of2 posteriormarginwithdistalclusterofminutelypectinate -4stoutspines,terminallywith3longand2shortspines setae, posterodistal margin strongly produced, dactyl and 1 short plumose setule. toothed on flexorsurface, closing onposterodistalproc- Pereopod 6 - Coxa rounded posteriorly, posterior ess of article 6 to form chelate gnathopod. margin lined with simple setae; article 2 subquadrate, Pereopod 3 - Coxa strongly convex anteriorly, pos- posteriormarginlined withsimple setae proximally and terior margin with 7 plumose setae, posterodistal angle distally,bare gapin center(present onmostspecimens), with 3 long, simple setae, anterodistal margin with 6 anteriormarginwithrow ofplumosesetae andwithrow shorter simple setae; article 2, distal half of posterior curving across lateral surface proximally, anterodistal margin with several groups ofsimple setaealong lateral marginwith3long,pectinatesetae;article4subtrianglu- surface,longplumosesetaeandseveralthinsimplesetae, lar, longerthan broad, anterior margin lined with dense posterodistal margin with 5 plumes and 1 short simple plumose setae occuring in medially placed diagonal seta, anterior margin with 5 short, scattered setules; rows, marginalspines stout, short, occuringingroupsof article 4, anterior margin lined with 9 plumose setae, 1 to 4, medial anterodistal angle with 1 long spine and anterodistal angle with a cluster of 3 simple setae, numerous plumed setae, lateral anterodistal angle with posteriormarginwith6groupsoflongplumosesetaeand 1 long spine, distolateral margin with 8 spines in row shortsimple setae proximally, distalportion ofposterior extending about one-quarter length of margin, center marginwithadenseclusterofmuchlongerplumosesetae distal margin with a group of 2 spines, posterior disto- and 3 shortsimplesetae; article 5 with aclusterof5 - 6 lateralmarginwithrowof4spines,posteriormarginwith simplesetaeonanterodistalmargin,posteriorlobeovate, 4 stout spines and a row of plumose setae, proximal lined with 15 stout spines, some withaccessory setules, section of margin narrowing abruptly, lateral surface lateral surface of lobe with 4 stout spines, posterior withclustersof2-4spines;article5subquadrate,.slightly margin with 4-5 long plumose setae; article 6 subrec- widerthan long with defining lobe at anterodistal angle, tangulaiwith13stoutspinesand 1 smallsetaonanterior anteriormarginwith3groupsof3-6spines,^terodistal and distal margins, posterior margin bare. lobe with 5 spines, distal margin with central row of 12 Pereopod 4 - Coxa broad, anterior margin strongly spines, posterodistal angle with cluster of 4 spines, convex, posterior margin with strongly angular lobe, posterior margin with 3 spines, lateral surface with 5 linedwithsimplesetae;article2shortwith4shortsimple groupsof1 -3spines,article6nakedanteriorly,posterior setaeon anteriormargin,posteriormarginwith 6simple marginwith5groupsof2-5 spines,terminalspines 10. setae and 2long plumed setae, posterodistal angle with Pereopod 7 - Coxa small, posterior lobe subacute, 2minutely pectinatesetae; article 3 with3posterodistal with simple setae ondistal margin; article 2ovate,with minutely pectinate setae; article 4 lined with posterior a cluster of proximal plumose facial setae, anterior marginal plumose setae and several scattered simple margin lined with plumed setae, distal half of margin setae,posterodistalanglewith8simplesetaeandalateral with4distallytaperedpectinatesetae, anterodistalangle row of 4 plumose setae, anterior margin lined with with 9 pectinate setae, posterior margin with scattered plumose setae, anterodistal angle with 2 simple and 3 short setules, orbare; article 4 much broader than long, minutely pectinate setae; article 5 with posteriorly di- proximal and distal margins nearly parallel posteriorly, rected circular lobe fringed with 11 stout spines and 7 widening anteriorly, anterior margin twice length of long simple setae; article 6 with 11 stout anterior mar- posteriorwith2groups of2-4spines,anterodistalangle ginal spines, 7 long simple posterodistal marginal setae with 8spines,proximalmarginlinedwithplumosesetae, and 1 distal marginal setule. posteriormarginwithcluster of 1 long and 2shortstout Pereopod 5 Coxa broad, posterior lobe slightly spines, 1 long plumose setae (broken ofO, 5 pectinate deeperandnarrowerthananterior,posteriormarginlined setae,posterodistal angle with 1 stoutspine,distomedial with simple setae; article 2, posteriormargin linedwith margin with row of 16 spines, distolateral margin with simple setae, anterior margin lined with plumose setae row of 10spinesextendingoverhalfthelengthofdistal 266 Foster and LeCroy margin, lateral and medial surfaces with scattered clus- Distribution ters oflong setae; article 6,posterior marginwith distal clusterof2stoutspinesand1pectinateseta,posterodistal Haustorius jayneae occurs along sand beaches from angle with 2shortlateral spines, row of4 longermedial Cape San Bias, Florida (Gulf County) to Mississippi spines, clusterofsimple setae on medial margin, poste- Sound. Itinhabitstidalpoolsandtheswashzoneseaward riorfacialspines2,anteriormarginal spines in6groups toadepthoftwometers;however,mostindividualsoccur of5 - 7 spineseach, medialsurfacewithoblique row of in depths less than one foot. 4 spines near anterodistal margin, lateral and medial surfaces with numerous clusters ofsimple setae; article Ecology 6anteriormarginalspinesin3groupsof2-4spineseach, posteriormarginalspinesin4groupsof1 -4spineseach, AtPanama City Beach,Florida,monthlydensities of medial surface with 1 group of 3 spines, lateral surface Haustorius jayneae and its distribution across the with 1 group of2 spines, terminal spines 7. nearshore zone were studied for a period of years by Pleopods-Pleopod 1,outerramuswith 15 segments, Saloman (1976) and Saloman and Naughton innerwith 12; pleopod2, outerramus with 17 segments, (1977;1978;1984). The swash zone population was innerwith 12; pleopod3 outerramuswith 16 segments, showntobethegreatestinMarchandAprilof1974-1975 inner with 13. with similarpeaks during May and June of 1976. In a Pleosome - With characteristics of the genus. seriesofstations,beginningintheswashzone,extending Uropod 1 - Ventromedial margin ofpeduncle with 2 throughaseriesofsandbars, and terminating atadepth clustersofsimplesetae,dorsalmarginwith1 simpleseta of9.1meters,H,jayneae occurredprimarilyintheswash and 1 stout spine proximally, 3 stout spines distally, zone and on the first sand bar (5.5% and 8.8% of all interramal area with 3 spines; outer ramus shorter than organisms collected, respectively). No specimens were inner with lateral spine groups 2-2"3-4, medial surface recoveredfrom the 9.1 meterstation. This conforms to with5groups oflongsimple setae,increasinginnumber thepatternobservedbySameoto(1969) forH. canaden- distally, terminal spines 6; inner ramus, ventrolateral sis at Sippewisett, Massachusetts, in that greatestdensi- marginalspines ondistalhalfin2groupsof3-7 spines tiesare foundinareasofcompletesaturationatlowtide, each, dorsal margin with 4 groups of simple setae, such as sand bars. Juveniles were present during all terminal spines 9. monthsandovigerousfemaleswerepresentinallsamples Uropod 2 - Dorsolateral margin ofpeduncle with a examined except those from January and May. rowofslenderspinesofvaryinglengthsinterspersedwith The study area displayed an annual temperature long simple setae, dorsomedial margin ofpeduncle with variation of 19.0 to 32.1 ®C andhad an average salinity distal clusteroflongplumosesetae; outerramus slightly of31.8ppt. Thesedimentsconsistedof99-100%quartz longer thaninner, lateral surfacewith3 clusters oflong sand(Sioman, 1976). During a laternine monthstudy simple setae, terminal group of long setae; inner ramus inthesamearea,HJayneaecomprised16,5%ofthetotal similar. populationoforganismsrecoveredfrom theswashzone, Uropod 3 - Peduncle with 9 (5 medial, 4 lateral) 55%oftheCrustaceaand99%oftheAmphipoda. Atthe spines; rami subequal, inner ramus with distal group of firstsandbar,H.jayneaecomprised34.1% ofallorgan- 3 spinesonmedial margin,2groupsoflongsimplesetae isms, 47% ofCnjstacea, and93% ofAmphipoda. May on lateral margin, terminally with 5 spines, numerous and June were peak population periods (Saloman and long, simple setae, 1 plumed seta; outer ramus 2-seg- Naughton, 1984). mented, proximal segment with 2 dorsomarginal and 1 Saloman et al. (1982) investigated the macroinfauna dorsodistal groups ofsimple setae, 6distoventralspines, of vegetated and unvegetated sediments within St, distal segment slightly shorter than proximal segment, Andrew Bay and reported an undescribed Haustorius thinner, with 7 terminal spines, numerous long simple from four localities. While tho.se specimens were not setae. available forstudy, one ofthe stations conformedto the Telson - Cleft one-third distance to base, lobes type locality ofH.jayneae. The locality, at West Pass subrcctangular with small proximolateral lobes bearing of St. Andrew Bay, was unvegetated 100% sand. 3spines,distalmarginwith9spines,submarginalcluster with 6 spines, dorsal surface with 1 long and 1 short Etymology penicillate seta on each lobe. This species is named in honor of Jayne E. Foster, Holotvpe Female SAB-e. 6.0 mm. St. Andrew Bav. whose patience and support for this project are greatly Florida appreciated. Similar to male except for the following: Variation Oostegites - Slender,increasing inlengthposteriorly on pereopods 2-4,verysmall onpereopod 5, marginal Within the samples examined from four locations on setae elongate, simple. the northern Gulfcoast,H.jayneae showedminorinlra- A Haustored Amphipod From The Gulf Of Mexico 161 specific variation (Table 1). Minor variations were Remarks observedinthenumberofaccessoryflagellumsegments, spination of the pereopods, and the spination of the Haustorius jayneae is most closely related to H, dorsolateralmargin ofthe peduncle ofiiropod 1. There canadenis Bousfield, 1962 from the American Atlantic was also a trend toward an increase in number of coast. Majormorphological differences between it and spines in all areas with increasing animal size. This otherknownspecies areshowninthekeyandinTables variability is to be expected in highly spinous fossorial 2 and 3. forms such as the Haustoriidae (Thomas and Barnard, 1984). KEY TO THE KNOWN SPECIES OF HAUSTORIUS (Modified from Bousfield, 1973) TABLE 1 IntraspedflcVariationin SelectedCharactersofHaustoriusjayneae SizeGroupingsofParatypes 4.0—5.0mm 5.1—6.0mm 6.1—8.0mm 8.41—10.0mm Character Range(Mean) OverallRange Antenna 1,# 4 4 4-5 4-5* 4-5 accessoryflagellum (4.0) (4.0) (4.1) (4.5) segments Mandiblepalp 3, 11-17 12-20 16-20 22-23 12-23 #combspines (13.0) (16.1) (16.6) (22.5) Peteopod5,article 5 5-8 5-9 6-7 5-9 4,#posterodistal (5.0) (6.4) (6.8) (6.5) spines Pereopod5, article 3 3 3-^*’*' 3 3-4 6,#anteriormarginal (3.0) (3.0) (3.3) (3.0) spinegroups Pereopod6,article 5-6 4-8 6-9 6-10 4-10 4,#posterodistal (5.3) (6.3) (7.6) (8.0) spines Pereopod7,article4, 1 1 1 1 1 #longmedialposterior (1.0) (1.0) (1.0) (1.0) marginalspines Pereopod7,article4, 6-8 6-11 9-18 9-10 6-18 #posterodistal (6.8) (8.6) (12.0) (9.5) spines Pereopod7,article5, 6 6-7 6-7 7 6-7 #anteriormarginal (6.0) (6.3) (6.4) (7.0) spinegroups *Two specimens,MISS-bandMISS-chad5segments Onespecimen,PK-fhad4groups Foster and LeCroy TABLE2 ComparisonofHaastoriusjayneaeandHaustorius canadensis Character H. canadensis H.jayneae Rostrum Acute,lessbroadbasally Subacute,triangular,wideatbase Pereopod5,article6 4—5 anteriormarginalspinegroups 3,occasionally4 spinegroups Pereopod6,article4 Longposteriormarginbefore Shorterposteriormargin,moredistal proximalnarrowing,6posteriorspines pointofproximalnarrowing,segment triangular, 3posteriorspines Pereopod6,article5 Anteriormargin roundedgentlyto Articlesubquadrate withadistinct distalmargin withoutclear anterodistaldefininglobe,lobewitha anterodistalangle,6spinegroups clusterof3 spines,distalandanterior alongcurve spinespresent Pereopod7,coxalplate Setaealongentireposteriormargin Setaeonposterodistalmarginonly Pereopod7, article4 Spinesondistolateralmargin limited Spinesondistolateralmarginmore toposteriorone-fourth ofmargin, widely spacedandextendingatleast closely spaced one-halflengthofmargin Uropod 1,peduncle 3—4proximalspines, and 1—2 1—2proximal spinesandoccasionally proximal setae 1 proximal seta 1. Uropod 1, dorsolateral margio of peduncle lined limited to posterior quarter of distal margin throughout out with stout spines; pereopod 7, article 4, H, canadensis Bousfield proximal margin rounding, continuous with posterior margin; EUROPEAN SPECIES 2 Pereopod 6, article 5, anterodistal angle with defining lobebearingaspinecluster;pereopod7,coxalplatewith Uropod1,dorsolateralmarginofpedunclewithproximal setae onposterodistalmarginonly, article 4, distolateral anddistal groups ofspines; pereopod7, article4,proxi- marginal spines extending to mid-margin mal margin sharply set off from posterior margin; //. jayneae n. sp. AMERICAN SPECIES 3 Acknowledgements 2. Accessory flagellum4+segmented; pereopod7,pos- terior margin of article 4 with 3-4 stiff spine groups The authors wish to thank Dr. Richard W. Heard of H. arenarius (Slabber) the GulfCoast Research Laboratory for technical assis- tanceandspecimensfromPeniidoKey,FloridaandHorn Accessory flagellum 3-segmented; pereopod 7, proxi- and Ship Islands, Mississippi (collected under contract mal andposterior marginofarticle4linedcontinuously totheNationalPark Service). Dr. Edwin J. Keppnerof with long stiff setae H. algeriensis Mulot Panama City Beach, Florida, also provided technical support. We thank Dr. Roger Lincoln of the British 3. Rostrum verylong, extending to the end ofantenna Museum, Dr. J. L. Barnard of the Smithsonian Institu- 1, peduncle segment 1 Haustorius “long rostrate tion,andDr. DeniseBellan-Santini oftheInstitutocean- form” ographique of Monaco for providing additional speci- mens and/or information. We also thank the Gulf Rostrum short, not exceeding midpoint of antenna 1, County,Florida,CountyCommissionfortheirassistance peduncle segment 1 4 atCapeSanBias. Webenefitedfrom andappreciatethe contributions of two anonymous reviewers. Many of 4. Pereopod 6, article 5, anterodistal angle broadly theirsuggestionswereincorporatedintothispaper. This rounding;pereopod7,coxalplatewithsetaealongentire research was supported in part by the National Park posterior margin, article 4, distolateral marginal spines Service (Contract #CA-5320-9-8001).