Description Of The Ghost Shrimp Sergio-Mericeae, A New Species From South Florida, With Reexamination Of S-Guassutinga (Crustacea, Decapoda, Callianassidae)

15 Pages·1995·7.8 MB·

by  R B Manning

PROCEEDINGSOFTHE BIOLOGICALSOCIETYOFWASHINGTON
108(2):266-280. 1995.
Description of the ghost shrimp Sergio mericeae, a new
species from south Florida, with reexamination of
S. guassutinga (Crustacea: Decapoda: Callianassidae)
Raymond B. Manning and Darryl L. Felder
(RBM) Department ofInvertebrate Zoology, National Museum ofNatural History,
Smithsonian Institution, Washington, D.C. 20560, U.S.A.;
(DLF) Department ofBiology, University ofSouthwestern Louisiana,
Lafayette, Louisiana 70504, U.S.A.
Abstract.—Sergio mericeae is here described from intertidal sandflats ofthe
AtlanticcoastofFlorida, whereitshareshabitatswithNeocallichirusrathbunae
and A^. grandimana. This new species, formerly identified with the Brazilian
species, Sergio guassutinga (until recently assigned to Neocallichirus), bears a
strongresemblancetoitsBraziliancounterpartinbodysize,theuniquedactylar
dentition ofthe majorchela, and most othermorphologicalfeatures. However,
these apparent sibling species can be distinguished on the basis ofbody col-
oration and subtle but consistent differences in the third maxilliped and major
cheliped.ImmaturespecimensfromLouisiana,TexasandTamaulipas,Mexico,
strongly resemble topotypic juveniles from Fort Pierce, Florida, and suggest
that S. mericeae ranges into the western GulfofMexico.
Uniqueness ofthe species described be- ed on by Biffar (1971), as many specimens
lowwas recognized in the course ofour on- upon which his earlier records were based
going effort to document diversity of in- were lost in a laboratory fire just prior to
faunal decapods inhabiting intertidal sub- publication ofhis work.
strates of the Indian River Lagoon on the Recent studies of the American Calli-
Atlantic coast ofFlorida. Our collecting ef- anassidae have revealed a number ofcases
forts in this region of marked tropical to wherespeciesformerlythoughttobeofwide
warm-temperate faunal transitions have distribution were actually complexes com-
employed yabby pumps (Hailstone «& Ste- prised of regionally endemized species
phenson 1961, Manning 1975) for extrac- (Felderetal. 1991, Felder&Manning 1994,
tion ofa speciose assemblage ofthalassinid Felder & Rodrigues 1993, Manning 1993).
ghostshrimpandassociated fossorial forms. In the context ofthose patterns, the previ-
Materials from thisregion haveledto com- ous report of the Brazilian Callianassa
parative studies of thalassinids from guassutinga Rodrigues from south Florida
throughout the western Atlantic, as well as (Biffar 1971) suggested such an extensive
systematic revisions and new distribution range that we were led to question the con-
records, especially for members ofthe Cal- specific assignment of its northern and
lianassidae (Felder & Manning 1994; Man- southernpopulations. AsmaterialsthatBif-
ning 1987, 1993; Manning & Felder 1986, farassignedtothisspeciesfromFloridawere
1991, 1992; Manning & Heard 1986; Man- for the most part destroyed in the afore-
ning & Lemaitre 1994; Rodrigues & Man- mentioned fire (see Biffar 1971), detailed
ning 1992). Collectionofnewmaterialsfrom comparisons with the Brazilian form were
Florida was essential in order for us to re- delayed until we could accumulate an ad-
examine the populations previously report- equate series of adult specimens from the
VOLUME NUMBER
108, 2 267
Roridapopulation. Inthecourseofmaking drigues, 1966, 1971].-Abele & Kim,
those collections, we photographically doc- 1986: vii, 26, 294, 296, 298, figs, a-c on
umented coloration in northern popula- 299.-Williams et al., 1989: 28, 61.
tions which differed markedly from report- "nearCallianassaguassutinga'\—Manning
ed coloration ofthe Brazilian species (Ro- &Felder, 1989: 16.
C
drigues 1966, 1971), and this further en- Callianassa(nr. guassutinga).—Rabalais
couraged us to undertake detailed etal., 1989: 35.
&
morphological studies and the present de- Sergio sp.-Staton Felder, 1995: 505.
scription ofa new species. Sergioguassutinga.—Manning&Lemaitre,
Material examined is listed by location 1994: 40 [Florida record only. Not listed
followedbydate, collector(coll), numberof and figured Brazilian materials].
=
specimens per sex and condition (mutl
mutilated, ov = ovigerous, immat = im- Type material—Holotype: North side of
mature), and museum number. Size is ex- Fort Pierce Inlet, Florida, island immedi-
pressed as postorbital carapace length (cl) atelywestofCoon Island, St. LucieCounty,
or total length (tl) measured in millimeters IndianRiverLagoon,intertidalsandflatjust
(mm). The holotype and some paratypes of shoreward of sparse seagrass, 27°28.2'N,
Sergio mericeaehave been deposited in the 80°18.8'W, 20 May 1994, coll D. L. Felder
National Museum of Natural History and W. D. Lee, 1 5 (cl 29.8 mm), USNM
(USNM), Smithsonian Institution, Wash- 268645.
ington, DC. Paratypes have been deposited Paratypes: Same site as holotype, 6 Mar
in the University of Southwestern Louisi- 1985, coll W. D. Lee and S. Petry, 1 6 (cl
ana Zoological Collections (USLZ), Lafa- 28.3 mm; tl 106 mm), USNM 268682; 5
yette, Louisiana, theHarborBranchOcean- Mar 1985, coll W. D. Lee and S. Petry, 1
ographicMuseum(HBOM;formerlytheIn- mutl S (cl ca 30 mm), USNM 268683; no
dian River Coastal Zone Museum, date, coll W. D. Lee and S. Petry, 1 9 (cl
(IRCZM), Fort Pierce, Florida, and the 31.1 mm;tl 115 mm),USNM268684;north
Florida Marine Research Institute Inver- side ofFortPierce Inlet, Florida, Dynamite
tebrate Collection (FSBC-I), St. Petersburg, Point site near Fort Pierce Inlet State Park,
Florida. Comparisons with the Brazilian St. Lucie County, Indian River Lagoon,
speciesSergioguassutingawerebasedupon 27°28.3'N, 80n7.8'W, 12 Aug 1989 (RBM
the published figures and descriptions by station FP 89-5), coll D. L. Felder and R.
Rodrigues(1966, 1971)andexamination of Brown, 1 5 (cl 20.4 mm), USNM 268685;
a mature female from Aracaju, Brazil 3 Jun 1993, coll D. L. Felder, 1 $ (cl 10.7
(USNM 268644), herein illustrated, as well mm; tl 35.8 mm), USLZ 3542; north side
as comparisons with a female topotype of Fort Pierce Inlet, Florida, Coon Island,
(USNM 221802), a male paratype (USNM St. Lucie County, Indian River Lagoon,
256886), a male from Praia de Pirangi-Sul, 27°28.2'N, 80°18.2'W, 3 Apr 1985, coll W.
Rio Grande do Norte, Brazil (USNM D. Lee and S. Petry, 1 c5 (cl 31.1 mm; tl
221810), and a female specimen from Na- 115.2 mm), USNM 268686; 16 Jul 1994,
tal, Rio Grande do Norte, Brazil (USNM coll W. D. Lee, 1 9 (cl 27.1 mm; tl 105.6
221804). mm), USLZ 3543; north side ofFort Pierce
Sergio Manning & Lemaitre, 1994 Inlet,Florida,northeastofCoastGumardSta-
tion, near exposed sand bar, 0.3 depth,
Sergio mericeae, new species
25 Apr 1972, coll H. B. Russell, 1 d (cl 29.7
Figs, la-f, 2a-f, 3a-f, 4a-f, 5a-g mm; tl 1 18 mm),HBOM 89:103; south side
—
Callianassaguassutinga. Biffar, 1971:651, ofFort Pierce Inlet, Florida, intertidal sand
653, 674, figs. 9, 10 [VirginaKey, Miami, barjust north ofand separated by shallow
Florida.NotCallianassaguassutingaRo- channel from U.S. Highway AlA causeway
268 PROCEEDINGSOFTHE BIOLOGICALSOCIETYOFWASHINGTON
between Fort Pierce and South Hutchinson coll D. L. Felder, W. D. Lee, and P. Mik-
Island, St. Lucie County, Indian River La- kelsen, 1 6 (cl 17.0 mm), USNM 268698; 1
goon, 27°27.7'N, 80°18.7'W, 23 Jul 1985 6 (cl 14.5 mm, photographic voucher),
(RBM station FP 85-4), coll R. B. Manning USLZ 3547, 2 66 (cl 13.4, 13.8 mm), 2 mutl
and D. L. Felder, 1 mutl 2 (cl ca. 29 mm), ov 22, FSBC-I 47980; 8 Sep 1985, coll W.
USNM268687; 12Aug 1986 (RBM station Lee and P. Mikkelsen, 1 6 (cl 16.0 mm),
FP 86-4), coll R. B. Manning, D. L. Felder, USNM 268699; 23 July 1994, coll D. L.
and W. D. Lee, 1 mutl 6, USNM 268688; Felder, J. M. Felder, R. D. Felder, and W.
15 Aug 1986 (RBM station FP 86-7), coll D. Lee, 222(cl 1 1.9, 18.5 mm),USLZ3548;
R. B. Manning, D. L. Felder, and W. D. Seaquarium Flats, Virginia Key, Dade
Lee, 1 mutl (5 (cl 13.7 mm), 2 ov 22 (1 mutl, County, Florida, 29 Feb 1964, coll S. Dob-
other cl 30.5 mm; tl 114.9 mm), USNM kin, 1 2 (cl 10.3 mm; tl 37.4 mm), USNM
268689; 2 Mar 1987 (RBM station FP 87- 122732.
2), coll R. B. Manning and W. D. Lee, 2 SS Other material examined. —Louisiana:
male (cl 9.1, 9.4 mm), USNM 268690; 3 Just off" Cat Island Pass, mouth of Terre-
Mar 1987 (RBM station FP 87-4), coll R. bonne Bay, 28°56.8'N, 90°33.7'W, trawl,
B.ManningandW.D.Lee, 1 mutl2,USNM depth of 12-13 m, 12 Jul 1984, coll N. N.
268691; 5 Mar 1987 (RBM station FP 87- Rabalais and students, 5 mutl immat (cl
6), coll R. B. Manning and W. D. Lee, 2 $6 6.5-7.9 mm), USLZ 3549. Texas: Port Is-
(cl 10.4, 17.5 mm), USNM 268692; 17 Apr abel,Texas, lowerLagunaMadrenearBraz-
1988 (RBM station FP 88-1), coll R. B. osSantiagoinlet, muddysandflatjustnorth
Manning and M. Schotte, 1 mutl 6 (cl ca. of mainland end of old abandoned cause-
15 mm), USNM 268693; 1 Jun 1993, coll wayto South Padre Island, CameronCoun-
D. L. Felder, 1 2 (cl 26.5 mm, dissected for ty, Jul 1991, coll D. L. Felder, J. M. Felder
hindgut study), USLZ 3544; 2 Jun 1993, and R. D. Felder, 1 mutl 2 (cl 10.4 mm),
coll D. L. Felder, 1 S (cl 12.3 mm, dissected USLZ 3550. Mexico: Barra del Tordo, Ta-
forhindgutstudy),USLZ3545; 6Aug 1993, maulipas, Mexico, depthca. 0.3 m, margins
coll D. L. Felder and J. M. Felder, 1 2 (cl of sandy Halodule flat just inside inlet at
14.0 mm), USLZ 3546; St. Lucie, Rorida, mouthofRioCarrizalestuary, 24May 1982,
intertidal unvegetated sand flat just inside coll D. L. Felder and R. K. Tinnin, 5 66 (cl
St. Lucie Inlet, Martin County, Indian Riv- 9.5, 9.7, 9.9, 10.6, 12.0 mm), 3 22 (cl 9.5,
er Lagoon, 27°10.5'N, 80°10.4'W, 11 Feb 10.6, 10.8), USLZ 3551 (two are photo-
1983 (RBM station FP 83-2), coll R. B. graphic vouchers).
Manning, W. D. Lee, and H. Schiff; 3 66 (cl Diagnosis.—Front ofcarapace with three
8.3, 9.2, 10.2 mm), USNM 268694; Lake small spinous anterior projections, usually
Worth Inlet, Florida, intertidal, sparsely subequalorwithmedialslightlylongerthan
vegetated, sandytoshelly-sandflatsonnorth laterals. Eyestalks broad, tapered over
side ofPeanut Island, Palm Beach County, length, usuallyterminatedinspine, tubercle
26°46.7'N, 80°2.9'W, 4 Mar 1987 (RBM or acute angle, often not reaching to distal
station FP 87-5), coll R. B. Manning and endoffirstantennularsegment. Thirdmax-
W. D. Lee, 3 22 (cl 10.6, 18.7, 30.0 mm), illiped with dactyl arched and propodus
USNM 268695; 10Aug 1987 (RBM station broad,heightofpropodusgreaterthanlength
87-8), coll D. L. Felder, W. D. Lee, P. Mik- ofdactyl; diagonal length ofmerus-ischium
kelsen, and R. Bieler, 1 6 (cl 12.5 mm), less than or equal to 2 times width atjoint
USNM 268696; 1 1 Aug 1987 (RBM station between these articles. Major cheliped of
87-9), con D. L. Felder and W. D. Lee, 2 adultswith inferior margin ofmerus armed
66 (1 mutl, other cl 27.2 mm), USNM proximallybyelongate process of2-3 fused
268697; 12Aug 1987 (RBM station 87-10), spines, beyond which is short gap in mar-
VOLUME NUMBER
108, 2 269
ginal dentition, lateral surface with low, closely opposed over proximal portion of
rounded longitudinal carina; carpus about midline, divergent terminally; weakly sin-
halfas long as palm; dactylus shorter than uous anterolateral margin arching from
palm, cutting edge with rectangular tooth broad base of eyestalk to anterior taper,
proximally, acute recurved tooth at mid- joiningmesialmarginanteriorlyin variable
length, and seriesofsmalleracuteteeth dis- terminus,endingasspinule,tubercleoracute
tally. Minor cheliped with dactylus usually comer; rarely with subterminal spinule or
longer than palm. Uropodal exopod with tubercleinadditiontoterminalone. Cornea
dorsalplatemuch shorterthanventralplate. dark, area ofpigmentation sexually dimor-
Telson with posteriormargin weakly emar- phic; inboth sexes, roundedcorneal surface
ginate. is small, subterminal, anterolateral in po-
Description.—Adults of relatively large sition, larger relative to eyestalk and more
size, with postorbital carapace lengths bulbousin immaturethaninadultanimals;
mm
sometimes >30 and total lengths oc- in adult males, pigmented area large, often
casionally >1 10 mm. diffuse, almost broad as stalk, often occu-
Frontal margin ofcarapace (Figs, la, 5a, pying much ofdistal third to % ofeyestalk;
b) with three anterior prominences, each in adult females and juveniles, pigmented
acute or terminated by short spine, median area smaller, more restricted to area of
ofwhich is slightly more produced on tri- rounded corneal surface.
angular base to form rostrum, lateral of Antennularpeduncle shorterand heavier
whichoverlie innermargins ofantennal pe- than antennal peduncle, terminal article
duncles; low, obtuse tooth on anterolateral slightly longer than penultimate and reach-
margin just lateral to outer margin of an- ing to or beyond midlength ofterminal ar-
tennal peduncle. Rostrum extending less ticleonantennalpeduncle; penultimateand
than V3 visible length ofeyestalks in dorsal terminal articles of peduncle with ven-
view. Carapace lacking rostral carina, with tromesial and ventrolateral rows oflong se-
distinct linea thalassinica, and with a de- tae, those ofventrolateral rowlonger, dens-
fineddorsalovalmarkedposteriorlybydeep er, andcontinuedonto ventralramusoffla-
transversecardiacfurrow, furrowextending gellum; ramiofflagellum subequalinlength,
anteroventrally to either side above linea 4-5 times length ofterminal article ofpe-
thalassinica as shallow sinuous groove de- duncle; dorsal ramus with sparse tufts of
marcating posterior half of dorsal oval. long setae, distal halfwith heavier articles
Shallow cervical groove originating imme- bearing dense tufts of short ventral setae,
diately below linea thalassinica on anterior articles comprising tapered tip with dense
halfofbranchiostegite and curved antero- line of short ventral aesthetascs. Antennal
ventrally, intersecting raised sinuous ridge peduncle with penultimate article subequal
in anteriorthird ofbranchiostegite; portion to or slightly longer than terminal article;
ofridge anterior to intersection positioned basal article with dorsolateral carina above
ventrolaterallyto roundedhepaticboss and laterally produced excretory pore; second
usually sculpted by weak crenelations on article with deep, diagonal ventral suture,
upper surface. Subantennular region ofep- distolaterally with single tuft ofsetae, small
istome with dense tuft oflong setae brack- rounded vestige ofdorsal scale articulated
eting those ofantennular peduncle. atjoint with third article; third article elon-
Eyestalks flattened, weakly concave dor- gate, narrower than second, slightly longer
sally, length equal to or slightly less than 2 than combined lengths of first two, proxi-
timesbasalwidth, indorsalviewtipsreach- molaterally with partially fused condylar
ing to or nearly to distal end of basal an- process articulated to distolateral extreme
tennal article; mesial surfaces of eyestalks ofsecondarticle;fourtharticlenarrowerthan
270 PROCEEDINGSOFTHEBIOLOGICALSOCIETYOFWASHINGTON
b,d,f,h,i c_
29.F8ig.mm1).,SUerSgNioMme2r6i8c6e4a5e,;nd,ewe,sfpeemciaelse,ptayrpaetmyaptee(rcilal2s6.f5rommm)F,orUtSPiLeZrc3e5I4n4l.et,a.FCloarriadpaa;cae-cf,rofn,tm,aelyeeshtoallkost,ypbeas(acll
antennal segments, dorsalview, setaenot shown; b, Majorchelipedofmaturemale, carpusandchela, external
surface; c, Major cheliped ofmature male, ischium and merus, external surface; d, Major cheliped ofmature
female, carpus and chela, external surface; e. Major cheliped ofmature female, ischium and merus, external
surface; f, Telson, uropods and part ofsixth abdominal segment, dorsal view. Sergioguassutinga (Rodrigues)
fromAracaju,Brazil,female(cl23.5mm),USNM268644;g,Carapacefront,eyestalks,basalantennalsegments,
dorsal view, setae not shown; h. Majorchelipedofmature female, carpus andchela, externalsurface; i, Major
chelipedofmaturefemale,ischiumandmerus,externalsurface;j, Telson,uropodsandpartofsixthabdominal
segment, dorsal view. Scale linesindicate 5 mm.
VOLUME NUMBER
108, 2 271
third; flagellum 2-2.5 times length of an- carpus short; propodus slightly arcuate,
tennular flagellum. heaviest distally, length almost 3 times
Mandibles (Fig. 2a) with large, width; dactylus short, about Vs length of
3-segmentedpalp, elongatedthirdarticle of propodus, with terminal brush ofstiff"bris-
palp slightly tapered and terminally round- tles; exopod phylloform, nearly as long as
ed,longsetaeonexternalanddistalsurfaces endopodalmerus,marginallyfringedbylong
ofsecond article and on proximal extensor setae; epipodsmall, sutures subdividinginto
surface ofthird, field ofshort setae on most 2 proximal lobes and minute trianguliform
ofextensorsurfaceandterminalendofthird terminal lobe. Third maxilliped (Figs. 2f,
article; incisor process with well-defined, 3a) without exopod; endopod with long,
terminally corneous teeth on cutting mar- dense setation on mesial margin, terminal
gin,teethlargest,lesscoalescedonproximal 3articlesalsowithlongsetationonextensor
two thirds ofcutting margin, internal sur- margins; length ofendopodal merus-ischi-
face with lip giving rise to molar process um about 2 times width; ischium subquad-
proximaltoincisorteeth,molarprocesswith rate, slightly longer than broad, diagonal
4-6smallmarginalteeth;paragnath(notfig- length in adults about 1.6 times width at
ured) rounded, scaliform, poorly sclero- suture with merus, proximomesial margin
tized, set against and below molar process. forming subacute comer, internal surface
First maxilla (Fig. 2b) with endopodal palp withpoorlydefined, longitudinallyoriented
long, narrow, terminal article deflected elevation bearing curved row ofsmall den-
proximally at articulation; proximal endite ticles; merus subtriangular, distinctly
densely setose on sinuous margin, terminal broader than long; carpus heavy and sub-
lobe additionally with field oflarge, termi- triangular, with setose lobe on flexor mar-
nally bifurcate setae; distal endite elongate, gin, internal surface with dense field offine
proximally narrow, broadening terminally setae in distal third; propodus large,
where armed with short stiff* bristles and subquadrate in adults, height often exceed-
fieldofshortsetae, somewithbifurcatetips; inglength, internal surfacewithnarrowme-
exopodite low, truncate and setose. Second dian field of fine, dense setae, opposable
maxilla (Fig. 2c) with endopod narrowed margin slightly emarginate; dactylus nar-
distally, first and second endites each lon- row,arcuate,inadultsdistinctlyshorterthan
gitudinally subdivided, internal surface of height of propodus, terminally with small
first endite fused to broad, rounded, mar- brush ofstiff"bristles.
ginally setose plate; exopod forming large, Branchial formula includes exopods and
broad, scaphognathite. Firstmaxilliped(Fig. epipods as described for first and second
2d) with proximal endite narrowly pro- maxillipedsabove;branchiaelimitedtosin-
duced, dentiform, marginally setose; distal gle rudimentary arthrobranch on second
endite robust, subquadrate, mesial half of maxilliped, pair ofarthrobranchs on third
externalsurfaceandmarginsheavilysetose, maxilliped, and pair of arthrobranchs on
longest setaeterminal, internal surface con- each ofthe first through fourth pereopods.
cave; exopod ovoid, divided by transverse First pereopods oftwo sides forming dis-
suture marking notch on mesial margin, similar chelipeds, major cheliped heavy,
longestsetaeinfieldonexternalsurfaceand massive in adults ofboth sexes (Fig. Ib-e),
mesial margin proximal to notch; epipod much less altered from minor cheliped in
large,broad, anteriorendtaperedtonarrow juveniles than in adults (Fig. 5c-f). Major
terminus. Second maxilliped (Fig. 2e) with cheliped ofadults strongly calcified; ischi-
long, narrow endopod; endopodal merus um slender, superior margin weakly sinu-
length exceeding 4 times width, flexor mar- ous, inferior (flexor) margin with row of
ginwithdensefringeoflong, close-setsetae; minutedenticles; merusabouttwiceas long
272 PROCEEDINGSOFTHE BIOLOGICALSOCIETYOFWASHINGTON
a,b,c,d,e
Fig. 2. Sergio mericeae, newspecies, typematerialsfromFortPierceInlet, Rorida;a-e, femaleparatype(cl
26.5 mm), USLZ 3544; f, male holotype (cl 29.8 mm), USNM 268645, right mouthparts. a, Right mandible,
externalsurface;b,Firstmaxilla,externalsurface;c.Secondmaxilla,externalsurface;d.Firstmaxilliped,external
surface;e,Secondmaxilliped,externalsurface,rudimentaryarthrobranchnotshown;f,Thirdmaxilliped,internal
surface. Scalelinesindicate 5 mm.
as high, superior margin weakly sinuous, length about %q ofheight, superior margin
sometimes with few minute tubercles prox- nearlystraight,formingthinunserratedkeel
imally, inferior margin more strongly ar- slightly overhanging internal surface, prox-
cuate, proximally with strongprojecting of- imoinferior margin regularly rounded in
ten bifurcate process of 2-3 fused spines, outline, serrations ofkeel most evident on
margindistaltoprocesswithshortunarmed internalsurface;propodusheavy,length(in-
regionbeyondwhichmarginislinedbysmall cluding fixed finger) in large adults about
inferodistally directed teeth; carpus broad, 1.7 timesheight, heightgreatestbasally, su-
relatively shorter and higher in adults than perior margin ofpalm forming unserrated
in immature specimens, in large adults keel, especially in proximal half, inferior
VOLUME 108, NUMBER 2 273
Fig. 3. Sergiomericeae, newspecies, typematerialsfromFortPierceInlet,Florida;a,b, femaleparatype(cl
26.5 mm), USLZ 3544; c-f, male holotype (cl 29.8 mm) USNM 268645. a. Right third maxilhped, external
surface, setae not shown; b. Minor cheliped, internal surface; c. Right second pereopod, external surface; d.
Rightthirdpereopod,externalsurface;e,Rightfourthpereopod,externalsurface;f.Rightfifthpereopod,external
surface. Sergio guassutinga (Rodrigues) from Aracaju, Brazil, female (cl 23.5 mm), USNM 268644: g, Right
third maxilliped, external surface, setae not shown; h. Minor cheliped, internal surface. Scale lines indicate 5
surface with serrated keel most developed to unarmed; dactylus (movable finger) sub-
proximally, usually with 2-3 sharp short equal in length to palm, prehensile margin
spinesorteethonexternalsurfacejustprox- atmidlengthwithlarge, hookedacute tooth
imal to gape; fixed fingerin adultswith pre- bearing a single setose punctum at its base,
hensilemarginrangingfromstronglyserrate separated proximallyby deep emargination
274 PROCEEDINGSOFTHE BIOLOGICALSOCIETY OFWASHINGTON
from a single heavy, quadrate basal tooth, minated in slightly comified tip hooked to-
and distally by another deep emargination ward external side, external surface densely
fromserratemarginondistalthirdoffinger, setose, setae arranged in transverse bands
finger terminated in acute, hooked tip. on superior half.
Minorcheliped(Fig. 3b)slender, elongate Fourth pereopod (Fig. 3e) subchelate, in-
in adults; ischium narrow, unarmed; merus ferodistal comer of propodus produced to
elongately ovoid, length subequal to or form short fixed finger; soft dense setation
slightly less than 2 times height, subequal on outer surface ofpropodus and dactylus,
to length of ischium; carpus rectangular, that of propodus divided into upper and
slightly longer than merus, length twice lower fields, setae slightly longer in lower
height, smooth; chela about as long as car- field which continues onto lower halfofin-
pus;palmsubrectangular,lengthslightlyex- ternal surface; dactyl terminated in narrow
ceeding height; fixed finger subequal in tip hooked toward external side.
length to palm, prehensile margin weakly Fifthpereopod (Fig. 3f) minutely chelate,
serrate; dactylus (movable finger) in adults opposable surfaces ofpropodusand minute
consistently exceeding length ofpalm, pre- dactylus excavate, spooned, terminally
hensile margin very weakly serrate. rounded, forming beak-like chela obscured
Second pereopod (Fig. 3c) chelate, patch- by dense fields of setation on distal Vi of
es oflong setae on inferior margin ofischi- propodus and superior surface ofdactylus;
um, most of flexor margin on merus and corneous prehensile lip ofpropodus pecti-
both margins of carpus lined with evenly nate.
spaced long setae, inferior margin ofprop- Anteriorabdominal somites smoothdor-
odus with similar long setae proximally, sally, surface sculptureofthirdthroughfifth
progressively more reduced in length and tergites progressively more pitted, eroded,
stiffened distally, subterminally becoming or undulated in appearance; second tergite
densepatchofshort, stiff"bristles;prehensile withtuftoflongsetaeonposterolaterallobe;
marginsofboth fingerscorneous, finelyand thirdthrough fifthtergiteseachwithasmall
uniformly microserrate along straight edge broadly transverse field ofvery soft dense
over most oflength in both, microserration setae on the lateral lobe; sixth with distinct
terminated distally in thickened corneous transverse, terminal, posteriorly facing
tips offingers; superior margin ofdactylus groove above telson.
slightlysinuous,withlongmarginalsetation First pleopod ofmale and female unira-
becoming increasingly shorter length dis- mous, composed of2 articles; in male (Fig.
tally, replaced by dense patch ofshort stiff" 4a), distal article subequal in length to or
bristles subterminally; external surface of slightly shorter than proximal, subdivided
carpus, propodus and dactylus with scat- into 2 lobes by weak longitudinal furrow,
tered patches ofshort setae. in mature male anterior lobe terminally
Third pereopod (Fig. 3d) merus length rounded, posterior lobe terminally acute
about 3 times width; carpus broadest dis- with tip directed anteroventrally; in female
tally, terminally with large patches oflong (Fig. 4b)proximalarticlesubequalinlength
setaeoverreachingpropodus; propoduswith to terminal article, terminal article with
strong proximally directed lobe on inferior weaklyproducedshoulderjustbeyondmid-
margin, lobe terminally with long distally length. Second pleopod ofmale and female
directedsetaegivingwaytosubdividedtufts biramous; in male (Fig. 4c), dense setation
of slightly shorter setae along inferodistal largely restricted to tufts on lateral margin
margin, superior margin with field oflong ofexopod, distal extreme ofexopod, lateral
setae, patternedtufts oflightersetae onout- margin ofendopod and appendix masculi-
er face ofarticle; dactylus tear-shaped, ter- na, appendix masculina weakly separated
VOLUME 108, NUMBER 2 275
fromandnotoverreachingendofdistallobe of live specimens).—Variable and fading
ofendopod, no evidence ofappendix inter- quickly to opaque white in alcohol. In life
na; in female (Fig. 4d, e), both rami with most adult specimens with violet pink to
long setae, appendix interna small and rose pink ground color, occasionally very
acutely tapered distally. Third to fifth pleo- pale; usually with darker pink to scarlet or
podpairs(Fig. 4f)forminglarge, posteriorly orange-red on the chelae, cardiac region of
cupped fans when coupled at mesial mar- carapace, dorsal tergites ofabdominal seg-
ginsofendopods;endopodofeachsubtrian- ments 1-2, mid-dorsal and posterior ex-
gular, appendix internaembedded into me- tremesofabdominaltergites3-5,telsonand
sial margin ofendopod. uropods. Sixth abdominal tergite usually
Telson (Figs. If, 5g) broader than long, with 2 faint, reddish longitudinal bands to
subhexagonal, broadest at lateral lobes at either side ofmidline in anterior %. Juve-
midlength or in anterior half, posterior niles often with striking scarlet red to rosy
emargination producing pair ofweak lobes red coloration almost overall, but also with
or obtuse posterolateral comers, each ter- pigment deepest in same body areas as in-
minated by a tuft oflong setae; dorsal sur- dicated for adults above.
face with low, lightly setose boss near each Known rangeandhabitat.—Known from
anterolateral comer, medially with subdi- intertidal to shallow subtidal in the Indian
videdshorttransversecarinaborderedpos- River Lagoon and along the lower Atlantic
teriorlybyline ofsetae. Uropodwith acute, coast ofFlorida, USA, and (on the basis of
posterolaterallydirectedspineonprotopod, juveniles only) from coastal GulfofMexico
spine overreaching anterolateral margin of localitiesinLouisiana,southTexas,andTa-
endopod; endopod broad, trapezoidal, maulipas, Mexico. The single immature
slightly longer than broad, dorsal surface specimen of Sergio collected from Maya-
with tuft of long setae near posterolateral guez, Puerto Rico, in 1934 (coll: V. Biaggi,
comer, setae of posterior margin longest Jr., tl 73 mm, USNM 77462) which was
posterolaterally; exopod with anterodorsal previouslyreportedasS.guassutingabyBif-
platefallingwellshortofdistalexopodmar- far (1971) may or may not be correctly as-
gin, distal edge of plate lined with short, signed to that species, but we must defer
thickspiniformsetaegradingtothinnerlon- this determination until additional, fully
ger setae of exopod margin and long stiff, mature and better preserved materials of
spiniform setae at posterodistal comer of thatsoutherlypopulationbecomeavailable.
plate, distal margin of exopod with dense While most specimens have been taken
fringe ofsetation, fringe diminishedandre- with yabby pumps from intertidal to shal-
placed by row of short spiniform setae on low subtidal substrates, specimens from off
posterior margin. Louisianawere taken in atrawl deployed at
Size.—Among the materials examined, a depth ofapproximately 12-13 m. In vir-
the largest male (cl 31.1 mm; tl 1 15 mm) tually all cases, the animals appear to be
and largest female (cl 30.7 mm; tl 1 15 mm; distributedwithin ornearinletsto the open
ovigerous) were both taken from the im- ocean. IninletsoftheIndian RiverLagoon,
mediate vicinity ofFort Pierce Inlet, Ror- wheretheyburrowalongsideNeocallichirus
ida. Eggs on ovigerous specimens are small rathbunae, they typically occupy less vege-
with sizes (max. diameter) after preserva- tatedareasofsandbars,oftenjustshoreward
mm
tion ranging from 0.58-0.62 for im- ofwhere larger mounds ofejecta mark the
mature eggs without developed eyespots to burrowsofA^. rathbunae. Atleastin shallow
mm
0.62-0.68 for more mature eggs with waters, adults ofSergio mericeae appear to
well developed eyespots. havemud-linedburrowswith surfaceopen-
mm
Color(from notes and color photographs ings6-10 indiameter, andmay ormay