Two new species of snapping shrimps from the Indo-Pacific, with remarks on colour patterns and sibling species in Alpheidae (Crustacea: Caridea)

16 Pages·2001·1.7 MB·English

by  Anker, A

THE RAFFLES BULLETIN OF ZOOLOGY200149(1): 57-72
© National UniversityofSingapore
TWO NEW SPECIES OF SNAPPING SHRIMPS FROM
THE INDO-PACIFIC, WITH REMARKS ON COLOUR PATTERNS AND SIBLING
SPECIES IN ALPHEIDAE (CRUSTACEA: CARIDEA)
Arthur Anker
MuseumNationald'HistoireNaturelle, BIMM, 55, ruedeBuffon, 75005Paris, France. Email: [email protected]
ABSTRACT. - Alpheus tricolor, and Alpheusfasqueli, two morphologically very close, but differently
coloured speciesofsnapping shrimps are described and illustrated. Descriptions are basedon specimens
imported from Indonesiaand Sri Lanka. Bothnew species belong to theA. edwardsii group, and can be
distinguishedfromallotherspeciesofAlpheusbyseveralfeaturesofthefirstandsecondchelipeds,frontal
region, third maxilliped, and most readily by theirconspicuous colourpatterns. These attractive shrimps
areregularlyimportedfromIndonesiaandSriLankatoEuropeandSingapore,sometimesunderthename
"Alpheus strenuus".
KEYWORDS. - Caridea, Alpheidae,Alpheus, cryptospecies, Indonesia, Sri Lanka, aquarium.
INTRODUCTION show slight differences in some morphological features
(proportions ofmajor chela, shape of scaphocerite, length
Through the courtesy of Dr. Peter K. L. Ng (National ofstylocerite). Extensive comparisons with related species
University of Singapore) the author received a freshly ofA.edwardsiigroupreportedfromIndonesia(deMan1911,
preserved specimen of an Alpheus obtained in one of D.M. & AH. Banner 1985), the Philippines (A.H. & D.M.
numerousfishimporthousesinSingapore.Accordingtofish Banner 1981, Chace, 1988), the South China Sea (D.M. &
dealers this specimen was imported from Bali, Indonesia. A.H. Banner 1978, Liu & Lan 1980, Jeng & Chang 1985),
PriortothepreservationDr.Ngmadeaseriesofcolourslides Thailand (AH. & D.M. Banner 1966), Australia (D.M. &
ofthe living shrimp. Several months later Mr. F. Fasquel AH.Banner1982),Hawaii(Banner, 1953),theIndianOcean
(Aquarium du Musee National des Arts d'Afrique et (Coutiere 1905, AH. & D.M. Banner 1983), and the Red
d'Oceanie, Paris)obtainedanotherspecimenwhichhekept Sea(D.M. & A.H. Banner 1981), showedthatboth species
alive in the aquarium, and ofwhich only amoult has been were until now undescribed. Theycanbereadily separated
preserved. This specimenwas possibly also imported from from allotherspeciesofA. edwardsiigroupbytheshapeof
Indonesia. Then, in May 2000, two freshly preserved the majorandminorchelae,andbyseveralothersubtle,but
specimens, one of which was in almost perfect condition, nevertheless reliable features. However, these species can
and two complete moults, were brought to the Museum be bestrecognized by their colourpatterns, which are very
National d'Histoire Naturelle by F. Fasquel. These conspicuous and unique not only among Alpheus and
specimens, obtained in Germany, were imported and with Alpheidae, but also among all Decapoda.
high probability collected in Sri Lanka. Together with the
specimens,theauthorreceivedcolourslidesoflivingshrimps
from Sri Lanka. Finally, in February 2001, four specimens MATERIAL AND METHODS
ofthesamespeciesweresenttomebyDr.Ng,whoobtained
themfromdiversinSriLanka,thusconfirmingtheoriginof TypesweredepositedintheZoologicalReferenceCollection
Fasquel's specimens. ofthe Raffles Museum ofBiodiversity Research, National
Univeristy ofSingapore (ZRC), and the Museum National
The study ofpresent specimens shows that they belong to d'HistoireNaturelle,Paris (MNHN). Abbreviationsusedin
two closely related species from the Alpheus edwardsii text:CL=carapacelength;TL= total length;CHL= Chela
group. The specimens with different colour patterns also length (measured from proximal margin to tip of fixed
Received 21 Jul 2000 Accepted 13 Mar 2001
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Anker: Two new species ofsnapping shrimps
finger); Mxp =maxilliped; P=pereiopod; WA =western welldevelopedlamella,lateralspinestrong,thick,verybroad
Atlantic; EA = eastern Atlantic; EP= eastern Pacific; IWP atbase;anteriormarginoflamellaslightlyconvex(Fig.3e),
=Indo-West Pacific outermarginslightlyconcave;carpoceriteslightlyexceeding
scaphocerite, reaching to distal margin of antennular
peduncles.
ORDER DECAPODA LATREILLE, 1803
Mouthparts typical for Alpheus. Mandible with 2-jointed
FAMILY ALPHEIDAE RAFINESQUE, 1815 palp,incisorprocessdistallybearingapproximately12teeth;
molar process very stout. Maxillula with palp bilobed,
Alpheus tricolor, new species inferiorlobebearing 1slenderseta,superiorlobenotsetose.
(Figs. 1-6) Maxilla, first and second maxillipeds without specific
features. Third maxilliped robust, not expanded; annexed
Material examined. - Holotype, I adult female, CL 13.5 mm, arthrobranch welldeveloped;epipodialplatewithacutetip,
ZRC.1999.1488, Bali,Indonesia,bydiving, Oct 1999,colI. P. K. posterior margin flattened, expanded, densely covered by
L. Ng (obtainedfrom dealers).
thickened,distallybluntsetae(Fig.6h);epipodlong,slender;
exopod slightly exceeding antepenultimate segment of
Alsoexaminedweremoults ofayoungmale (CL9mm, CHL IQ
mm) importedfrom SriLanka, andanotherspecimen,probablya endopod; ultimate segment very setose, distally unarmed.
young female (CL IQmm) importedfrom Indonesia.
Major cheliped with merus stout, ventrally flattened, with
Diagnosis. - Carapace setose; rostrum acute, carinate, small spines on mesial margin, distally with strong tooth;
reaching to distal margin offirst antennular article; orbital superiormargindistallywithsharptooth;carpus veryshort,
hoods unarmed; adrostral furrows shallow, not abruptly cup-shaped, without distal teeth; chela about 2.5 times as
delimited. Second antennular article not elongated; long as high; palm about 1.8 times longer than dactylus;
stylocerite reaching beyond first article. Basicerite with superior transverse groove shallow; proximal shoulder
strong ventro-lateral tooth; carpocerite stout, slightly rounded, not overhanging groove; longitudinal grooves on
exceedingscaphocerite;lamellaofscaphoceritenotreduced, eachlateralsideofpalmshallow;inferiortransversegroove
with anterior margin concave; lateral spine very broad at absent; fixed finger with tip curved, sharp; dactylus with
base.Thirdmaxillipedwithepipodialplatebearingnumerous sharp tip; plunger short, obliquely truncated, distal surface
thickened setae. Firstchelipeds with merus bearing strong flattened, with shallow depression; adhesive discs on palm
disto-mesialtooth;chelawithsuperiortransversegrooveof anddactylussmall.Minorchelipedwithchelaslender,about
major chela shallow, proximal shoulder not overhanging 5timeslongerthanhigh, dactylusbalaeniceps(lateralridge
groove;inferiorgroovelacking;longitudinalgroovesoneach ofdactylus fringed with setae), not laterally expanded.
side ofpalm shallow; ratio palm to dactylus equal to 1.8;
plungershort, obliquelytruncated; minorchelabalaeniceps Second chelipeds robust, somewhat elongated; ischium
in both sexes. Second pereiopod with first carpal article relativelyshort;meruslongerthanischium;carpuscomposed
distinctlylongerthansecond.Thirdpereiopodwithischium of5 articles with ratio approximately equal to: 1: 0.6: 0.4:
armed, merus unarmed, dactylus simple, conical. Telson 0.4: 0.6;firstcarpalarticle about3timeslongerthanbroad;
broad,distallyslightlytapering,with2pairsofdorsalspines; chelaaslongasfirstcarpalarticle,fixedfingeranddactylus
posteriormarginweaklyconvex,with2spinesateachangle; with numerous setae, most ofthem inserted in tufts. Third
dorsal surfaces oftelson and uropods very setose. to fifth pereiopods robust; ischium ofP3 and P4 each with
movable spine; merus and carpus unarmed, without
Description. - Body not especially compressed. Carapace projections;propodusarmedwithrowsofspinesasfollows:
smooth,latero-anteriorlywithshallowgrooves,dorsallywith P3:9+distalpair,P5:5+distalpair;dactylussimple,curved,
numerouserectsetae;pterygostomialanglerounded;cardiac with subapical portion abruptly narrow (Fig. 5g).
notchverydistinct. Rostrumwelldeveloped, acute, slightly
descendant; tip reaching to distal margin offirst article of Abdomen without specific features, surface ofeach somite
antennularpeduncle; rostral carinareachingbeyondorbital bearing conspicuous setae proximal to dorso-posterior
hoods,continuedbyinconspicuous,flattenedridgetoabout margin.Uropodalexopodwithstronglateralspine,andwell
posterior third ofcarapace; adrostral furrows, not abruptly developed, sinuous diaresis; endopod without specific
delimited;orbitalhoodsinflated,roundedanteriorly,lacking features.Telsonbroad,taperingdistally,with2pairsofdorsal
teeth. Corneas well developed, pigmented; eyes with small spineslocatedindeepdepressions;posteriormarginslightly
anterior processes, visible in lateral view (Fig. 3b). rounded, with 2 pairs of lateral spines, inner spines more
than length of outer spines; numerous long setae between
Antennular peduncles stout; stylocerite with acute tip, lateral spines (including a row ofsuperiorly situated, erect
overreachingfirstanennulararticle;ventralantennularcarina setae); latero-inferior margins fringed with short plumose
well developed, distally with small acute tooth (Fig.3c); setae; anal tubercles well developed. Branchial formula
secondarticlenotespeciallyelongated, slightlylongerthan typicalforgenus, with I arthrobranchonMxp3and5strap
third article; outer flagellum biramous, shorter ramus like epipods on Mxp3 and PI-4.
composed of 3-4 free segments. Antenna with basicerite
bearingacute, ventro-Iateraltooth; scaphoceritebroad,with Coloration.- Carapacemostlyyellow-orange,laterallywith
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THE RAFFLES BULLETIN OF ZOOLOGY 2001
three conspicious, circular or elongated white patches, Biology. - The author could observe the behaviour of the
disposed as illustrated (Fig. la, lb; 2a). Rostrum reddish livingspecimenofA. tricolor,newspecies,intheaquarium.
orange; orbital hoods translucent; thin red line runs along The shrimp spent most of the time in its burrow under a
posterior branchiostegial margin. Antennal and antennular boulder,butcameoutwhenpiecesoffoodweredistributed.
peduncles orange-red, both flagella whitish. Mouthparts Itdidnotmakeanyattemptto associatewithapartnergoby
mostlycolourless,butpalpandcarideanlobeofMxpl, and (Amblyeleotris sp.) also presentin the aquarium. The goby
most of Mxp2 reddish. Mxp3 uniformly reddish-orange. obviouslypreferredtosharetheburrowwithAlpheusbellulus
Majorandminorchelipeds orange-red; merus distally with Miya & Miyake, 1968, a true partner shrimp.
white patch across outer angle and mesial spine; chelae
progressively lighter to almost white on tips of fingers;
plunger ofdactylus white; medio-superior margin ofpalm AlpheusJasqueli, new species
purplish,especiallyinmajorcheliped.Inyoungerindividuals (Figs. 1-6)
fingers anddistalportionofpalmconspicuouslywhite(Fig.
1b).Followingpereiopodsuniformlyorange-red.Abdominal Material examined. - Holotype, 1male, CL 17.5 mm, MNHN
13609, imported from Sri Lanka, co1l. F. Fasque1 (obtained in
segmentsdorsallyyellow-orange,latero-ventrallydeepred,
Niirnberg, Germany).
with three large and one smaller rounded white patches,
disposed as illustrated (Fig. 2a). Pleopods with protopod Paratypes, 1male, CL 14.5 mm, MNHN 13610,samedata as for
whitish, rami orange. Tail fan deep red, with broad white holotype; 1male,CL15.8mm,ZRC2001.1054,offColombo,Sri
band across proximal half; margins ofuropods and lateral Lanka,obtainedfromdivers,Jan.2001,coil.P. K.L. Ng;2males,
spine whitish; setaefringing uropods andtelsonproximally CL15.0and15.3mm,and1female,CL15.0mm,ZRC2001.1055,
Trincomalee,SriLanka,fromaquariumdivers,Feb.2001,co1l. P.
dark red, distally whitish.
K. L. Ng
Measurements. - Holotype: CL 13.5 mm,TL36mm,CHL
Diagnosis. - Carapace slightly setose; rostrum acute,
16 mm.
carinate,distinctlyexceedingfirstantennulararticle;orbital
hoods unarmed; adrostral furrows shallow, not abruptly
Etymology. - Species named after its characteristic colour
delimited. Second antennular article slightly elongated;
pattern consisting ofthree colours: white, red and orange.
styloceritenotexceedingfirstarticle. Basiceritewithstrong
ventro-lateral tooth; carpocerite stout, slightly exceeding
Remarks. - As mentioned above I had the possibility of
scaphocerite; lamella of scaphocerite not reduced, lateral
examining two moults of further specimens of Alpheus
spine with slightly broadened base. Third maxilliped with
tricolor, new species, which unfortunately could not be
epipodial plate bearing numerous thickened setae. First
preserved for this study. Although much smaller these
chelipedswithmerusbearingstrongdisto-mesialtooth;chela
specimensagreewellinmostmorphologicalfeatures andin
with superior transverse groove of major chela shallow,
colourpatternwiththeholotypespecimen.Somedifferences
proximal shouldernotoverhanginggroove; inferiorgroove
however, are noteworthy. The first moult (corresponding
lacking;longitudinalgroovesoneachsideofpalmshallow;
specimen, collectedin SriLanka was still alive) belongs to
ratiopalm/dactylusequalto 1.25;plungershort,obliquely
a young male (CL 9 mm, CHL 10 mm), and agrees almost
tuncated; minor chela balaeniceps in both sexes. Second
perfectlyinalmostallpointswiththeholotype.Asexpected,
pereiopod with first carpal article distinctly longer than
theminorchelaofmalesisclearlybalaenicepsinA. tricolor,
second. Third pereiopod with ischium armed, merus
n. sp., as is thecasein females. Theappendix masculinais
unarmed, dactylus simple, conical. Telson broad, distally
slenderandshort,notextendingbeyondtheappendixinterna.
slightly tapering, with 2 pairs of dorsal spines; posterior
The unusual ventral incision present on each second
margin weakly convex, with 2 spines ateach angle; telson
abdominal pleura ofthe holotype is absent in this and also
and uropods setose.
in following specimen. Thus, this incision couldbe simply
a genetic abnormality of the holotype specimen, or, less
Description. - Body not compressed. Carapace smooth,
probable, be developed only in largerindividuals ordue to
latero-anteriorly with shallow grooves, dorsally with
other cause.
scatteredsetae;pterygostomialanglerounded;cardiacnotch
well developed. Rostrum well developed, slightly
The second moult corresponds to a specimen ofunknown
descendant;tipacute,extendingbeyonddistalmarginoffirst
sex (CL 10 mm), which was importedfrom Indonesia. The
antennular article; rostral carina sharp reaching beyond
telson ofthis specimen has only 3dorsal spines insteadof
orbital hoods, continued by slight, flattened ridge to about
usual 4. The minor chela is not distinclty balaeniceps; the
posterior third of carapace; adrostral furrows deep, not
usuallongitudinal,slightlyobliqueridgeispresentonlateral
abruptlydelimited;orbitalhoodsinflated,roundedanteriorly,
sidesofthedactylus,butitis notfringedbythickenedsetae,
unarmed. Corneas well developed, pigmented; eyes with
typical for balaeniceps chela (Fig. 5c). Assuming that the
small anterior processes, visible in lateral view.
specimenwasayoungfemale,theabsenceofthebalaeniceps
condition could eventually be explained by its gradual
Antennularpeduncles stout; styloceriteacute, overreaching
development in females. The colour of the corresponding
firstantennulararticle; antennularcarinaasillustrated(Fig.
living specimenis less intense andwith morepurpleonthe
3h); second article not especially elongated, only slightly
chelae, but otherwise agrees well with that ofholotype.
longer than third article; outer flagellum biramous, fused
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Anker: Two new species of snapping shrimps
portion havingabout 20segments, shorterramus composed almost 5 times longer than broad; ratio of carpal articles
of 3-4 segments. Antenna with basicerite bearing strong, approximatelyequal to J:0.55:0.25: 0.25: 0.40;chelamuch
acute ventro-Iateral tooth; scaphocerite broad, with well shorter(about half) than first carpal article, fixed finger and
developed lamella,antel;ormarginslightlyconvex,narrower dactylus with numerousdense tufts ofstrongsetae. Third to
thaninA. tric%r;outermarginconcave;lateralspinestrong, fifth pereiopods similar to those ofA. tric%r; ischium of
less broadat basethan inA. tric%r; carpoceritereaching to P3and P4each withsmall movablespine; merusandcarpus
distal margin of antennular peduncles. Mouthparts as unarmed, without projections; propodus of P3 armed with
described for A. tric%r. Incisor process of mandible with spines (8 + distal pair); dactylus simple, conical, curved,
less than I0 blunt teeth. Epipodial plate on coxa of third subapically with trace ofsecondary unguis.
maxilliped apparently bearing more thickened, blunt setae.
Abdominal segments and caudal fin very similar to A.
Majorcheliped similarto thatofA. tric%r. Merus slightly trie%r. Uropodalexopod withmoderatelydeveloped lateral
crenellated on mesial margin, without teeth, distally with spine,diaresiswell marked,sinuous.Telson broad,tapering
strong mesial tooth and sharp superior tooth; carpus very distally, with 2 pairs of dorsal spines; posterior margin
short; palm ofchela about 1.25 times longer than dactylus, slightly rounded, with 2 pairs of lateral spines. Branchial
withsuperiortransversegroove;proximal shoulderrounded, formula as described for A. frie%r.
not overhanging transverse groove; longitudinal groove on
eachlateralsideshallow; inferiortransversegroovelacking; Coloration. - Carapace bright red, with circular and more
fixed finger with tip curved and sharp; plunger ofdactylus elongated, whitish patches, as illustrated (Fig. Ic, Id; 2b);
asdescribedforA. frie%r; adhesivediscssmall.Maleminor rostrum red; orbital hoods transparent. Antennal and
cheliped balaeniceps, laterally not expanded, tips broken in antennular peduncles reddish, both flagella purplish red.
holotype(Fig.5i),entireinall maleparatypes(Fig. 5j);palm Mxp3 uniformly reddish. Major and minor chelipeds red,
with slightly indicated superior groove; female minor merusdistallywithwhitepatchacrossouterangleand mesial
cheliped unknown. spine, chelae deep red, proximally lighter, with white tips
offingers and conspicuous whitepatch on dorsal margin of
Secondchelipedsrobust,elongated,leftslightly more robust dactylus, plunger reddish. Following pereiopods uniformly
than right;carpusmoreslenderthan inA. tric%r, firstarticle red. Abdomen red; pleura ventrally deep to bordeaux-red;
Fig. I. Alpheustricolor, new species (a, b)and Alpheusjasqueli, new species(c, d): a, holotypeofA. trieolor(ZRC. 1999.1488), photo
by P. K. L. Ng; b, younger individual (not preserved); c, d paratypeofA.jasqueli in dorsal and lateral views (MNHN J3610), photo by
F. Fasquel. All photos taken in aquarium.
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THE RAFFLES BULLETIN OF ZOOLOGY2001
..: .' .. ' .....-.-:" ."
OS-cm
Fig. 2. Alpheus tricolor, new species (a) andAlpheusfasqueli, new species (b): colour patterns ofcephalothorax and abdomen (after
freshly preservedholotype specimens). Scale: a- I mm, b- 5mm.
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Anker: Two new species of snapping shrimps
b
Fig. 3.Alpheustricolor,new species(a-e) andAlpheusJasqueli,newspecies(f-j):a, f, frontalregionin dorsal view; b,g,same,inlateral
view;c,h, antennule;d, secondabdominal pleurite;e,j,scaphocerite,i,flagellumofantennule. a,bandf, gfromholotypes,otherfigures
from moults. Scales: c, e, h, i,j - I mm; a, b, g, f- 5 mm, d- withoutscale.
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THE RAFFLES BULLETIN OFZOOLOGY2001
d d
be
et
aSC/n
e
Fig.4.Alpheustricolor, newspecies(a-d) andAlpheusfasqueli,newspecies(e-g).Majorcheliped(holotypes): a, outerview,b,e,chela,
outerview; c, f, chela, innerview; d, g, dactylus. Scales: a, b, c, d- I mm; e, f, g- 5mm.
63
Anker: Two new species ofsnapping shrimps
-
b b
c
..'.-....-....:.::~.:.'.'.
~
- n
/
-
f h
Fig. 5. Alpheustricolor, newspecies (a-h)andAlpheusJasqueli, new species(i-n): a-j small chela, inouter(a,i,j) and inner(b) views,
c;detailsoffixedfingeranddactylus;d,secondpereiopod;e,same,chela;f,I,m,thirdpereiopod;g,n,same,dactylus;h,fifthpereiopod,
distalpropodusanddactylus;k, secondpereiopod,carpusandchela.a,b,d-h,i,k,I,n,holotypes;j,m,paratype;c,frommoult. Allscales
- I mm, exceptfor i,j, I, m- 5mm.
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THE RAFFLES BULLETIN OFZOOLOGY2001
-
i
Fig.6.Alpheustricolor,newspecies(a-k)andAlpheusfasqueli, newspecies(I-n):a,mandiblejb,maxillulajC,maxilla;d,firstmaxilliped;
e, secondmaxilliped; f, third maxilliped; g, same, coxaand arthrobranch; h, I,m, same, detailofepipodial plate; i, telson,j, uropod; k,
appendix interna; n, caudal fan, setae omitted. a-g, i-k, n, holotype; h, I, m, from moult. All scales- I mm, exceptfor n- 5 mm.
65
Anker: Two new species ofsnapping shrimps
first four pleura each with medium-sized white patches; conical,withtraceofsecondaryunguis;epipodialplatewith
fourth and sometimes third segments with white anterio dense,bluntsetae;plungerofdactylus short, truncated. The
dorsalpatch. Pleopods withprotopodwhitish andramired. conspicuous colour patterns including dark red zones on
Uropodsred,withwhiteprotopod;lateralspinealsowhitish. abdominal segments, containing large white spots, are also
Telson entirely red; setae fringing uropods and telson diagnostic.
whitish-yellowish.
The most important morphological characters of both new
Measurements. - Holotype, largest of all available species are the absence ofinferior saddle on major chela,
specimens, has CL 17.5 mm, TL44 mm, and CHL22 mm. andtheminorchelabeingbalaeniceps-shapedinfemale. To
my knowledge only two species from A. edwardsii group
Etymology. - Named after Frederic Fasquel (Paris), havebothofthesefeatures: A. balaenodigitusD.M. & A.H.
enthusiastic photographer and collector of shrimps, who Banner, 1982, andA. pareuchirus imitatrix de Man, 1910.
obtained numerous rare specimens ofalpheid shrimps for A.balaenodigitusdiffersfrombothA.tricolorandA.fasqueli
the MNHN. in having a more slender second pereiopod, with different
ratio ofcarpal articles (second longer than first), different
proportionsofmajorchela,andmuchmoreelongatedsecond
DISCUSSION antennulararticle.A.pareuchirusimitatrixcanbeseparated
from A. tricolor and A. fasqueli by the dactylus of major
Alpheustricolor, newspecies,andA.fasqueli, newspecies, chela being more elongated, bearing smaller plunger, the
appeartobewellknowntotheimportersoftropicalanimals proximalshoulderofpalmslightlyoverhangingsaddle,and
for the marine aquarium in Europe. It is possible, that the the second pereiopod being more slender.
shrimps are collectedbydiving at oneorseveral localities,
wheretheymightberelativelycommon,andthendistributed Intheabsenceofminorcheliped,A. tricolorandA.fasqueli
tothedealers allaroundtheworld. Thetwonewspeciesare couldbeconfusedwithA. spatulatus A.H. & D.M. Banner,
knownunder severalLatin names in the aquarium-oriented 1968, andA. proseuchirus de Man, 1908. The first species
literature. is readily distinguished by several features including a
spatulate dactylus on third pereiopod, sharp tooth on
Baensch& Debelius(1992: 498)reportedAlpheustricolor, proximal shoulder of palm of major chela, and strong,
new species under the names «Alpheus sp.» and «Alpheus elongatedrostrum. ComparedtoA. tricolorandA.fasqueli,
strenuus»(notDana, 1852),andprovidedtwocolourphotos A. proseuchirus has a very differently shaped major chela
showing obviously the same species. The species was (A.H. & D.M. Banner, 1966: 129,fig. 47),whilethe second
reported as living with the goby Amblyeleotris pereiopodsaremoreslender.A. leptochiroidesdeMan, 1909
gymnocephala. This statement is certainly incorrect, since seemstobedifferent fromA. tricolorandA.fasqueli inthe
the speciesshows noparticularfeatures ofaspecieshaving proportions ofthe major chela (especially the height), and
burrowinglife style, e.g. the subspatulatedactylus on third by the weak inferior groove proximal to the fixed finger.
to fifth pereiopod. Busson (1998: 42), provided a colour
photo of Alpheus tricolor under «A. strenuus», and The numerous setae on the epipodial plate of the third
mentionedthatthespeciesisdistributedin"EasternPacific, maxilliped (Fig. 6h), present in both new species, are
frequently encountered in the region of the Hawaiian conspicuous, but not unique to A. tricolor and A. fasqueli.
Islands". F. Busson (pers. comm.) obtainedthis apparently To my knowledge the only other species with similarly
erroneous data from the French edition of the above developed setae on the epipodial plate is A. exilis Kim &
mentionedbookbyBaensch& Debelius(1992). Finally,A. Abele, 1988, described on two specimens from Galapagos
fasqueli was recently illustrated underthe name «Alpheus IslandsandMexico.Withoutconsideringthefirstpereiopods,
bisincisus» (not de Haan, 1849) by Debelius (1998: 272), whichwerelackingin A. exilis,thisspeciesisdifferentfrom
but the indicated locality «Gubal northern Red Sea» is A. tricolor and A. fasqueli in having orbital hoods armed
erroneous,thespecimenonthephotowasactuallyimported with acute teeth, and antennular peduncles elongated.
from Indonesia (H. Debelius, pers. comm.).
A. tricolor is morphologically so close to A. fasqueli, that
The morphology of the major chela clearly indicate that the only feature to distinguish them easily is the colour
AlpheustricolorandA.fasqueliaremembersofA. edwardsii pattern. However, there are also some very slight but
group, butit is closelyrelated neithertoA. strenuus Dana, apparentlyconstantmorphologicaldifferences.Therostrum
1852, nortoA. bisincisusde Haan, 1849. Both species can ofA.fasqueliisslightlylongerthanthatofA. tricolor.Also,
be distinguished from all the otherIndo-Pacific species by in A.fasqueli the stylocerite is shorter than in A. tricolor,
the combination of the following characters: superior while the base ofthe lateral spineofscaphocerite seems to
transversegroove ofmajorchelanotoverhung byproximal be much broader in A. tricolor than in A. fasqueli. The
shoulder; inferior transverse groove absent; minor chela general shape of major chelae is almost identical, but the
balaeniceps in both sexes; frontal region with rostrum proportionsareslightlydifferent, e. g. thepalmisabout 1.8
reaching atleastto distal margin offirst antennulararticle; times longerthanthedactylus inA. tricolor, whilethepalm
antennularpeduncleswithsecondarticleweaklyelongated; isonly 1.25timeslongerinA.fasqueli. Thedistalportionof
second pereiopod robust and elongated; dactylus simple, thefixedfingerissomewhatshorterinA.fasquelithaninA.
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