Two New Species of Sponge-Dwelling Snapping Shrimp from the Belizean Barrier Reef, with a Synopsis of the Synalpheus brooksi Species Complex

2006·0.68 MB·English

by  Kenneth S. Macdonald

PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY
CENTRAL PARK WEST AT 79TH STREET, NEW YORK, NY 10024
Number 3543, 22 pp., 16 figures December 7, 2006
Two New Species of Sponge-Dwelling Snapping
Shrimp from the Belizean Barrier Reef, with
a Synopsis of the Synalpheus brooksi Species Complex
KENNETH S. MACDONALD III1 AND J. EMMETT DUFFY2
ABSTRACT
Two new species of sponge-dwelling snapping shrimp in the genus Synalpheus are described.
SynalpheuscarpenteriisbasedonspecimenscollectedfromtheBelizeanBarrierReef,theExuma
IslandsoftheBahamas,andtheAtlanticCoastofPanama,whileSynalpheusruetzleriisbasedon
specimenscollectedfromtheBelizeanBarrierReefandtheAtlanticCoastofPanama.Bothspecies
belong to a group of closely related shrimp (the ‘‘Synalpheus brooksi complex’’) that includes
Synalpheusbrooksi,Synalpheusbousfieldi,Synalpheuschacei,andpossiblyadditionalundescribed
species. All species in the complex are remarkably similar in morphology, but Synalpheus
carpenteriisreadilyrecognizablebyitsbrilliantorangecolorinlife,itshabitationsolelyinsponges
ofthegenusAgelas,itssquat,wide-basedtelson,andtheshortlateralspinesofitsscaphoceriteand
basicerite.Synalpheusruetzleriappearsuniquewithinthecomplexinpossessingawell-developed
bladeonthescaphocerite.SpecimensofSynalpheusbrooksiandS.bousfieldifromBelizeandother
localities are also figured tofacilitate separation ofmembers of thebrooksi complex.
INTRODUCTION R´ıos,personalobs.)thatinhabittheinterstices
ofcoralrubble,theinternalspacesofsponges,
Snapping shrimp in the genus Synalpheus and, in the Indo-Pacific, the arms of crinoid
Bate, 1888 are diverse components of the echinoderms (Beebe, 1928; Pearse, 1932;
cryptic fauna of coral reefs and other tropical Bruce, 1976; Duffy, 1992). These shrimp are
marine ecosystems worldwide (Felder and small (usually ,2 cm in length) and reclusive
Chaney 1979; Reed et al., 1982). The genus and are often among the most abundant
includes more than 150 species (Chace, 1988; cryptofaunal macroinvertebrates in reef envi-
1DivisionofInvertebrateZoology,AmericanMuseumofNaturalHistory([email protected]).
2SchoolofMarineScienceandVirginiaInstituteofMarineScience,TheCollegeofWilliamandMary,GloucesterPoint,
VA([email protected]).
CopyrightEAmericanMuseumofNaturalHistory2006 ISSN0003-0082
2 AMERICAN MUSEUMNOVITATES NO. 3543
ronments (Pearse, 1932; Ru¨tzler, 1976). the authors and colleagues using scuba diving
Despite their abundance and diversity, the equipment. Sponges were identified whenever
systematic relationships and taxonomy of the possible. Lists of material examined are not
genus Synalpheus remain poorly resolved. comprehensive; additional specimens in the
InthewesternAtlantic,thegenusSynalpheus VIMS collection also were examined. Type
isdominated by speciesin theGambarelloides specimens and voucher material are deposited
group (Coutie`re, 1909; Dardeau, 1984), a in the National Museum of Natural History,
monophyleticclade(Morrisonetal.,2004)that Smithsonian Institution, Washington, DC
islargelyendemictothatregion.Speciesinthe (USNM); the American Museum of Natural
gambarelloides group are obligate sponge- History(AMNH);andintheVirginiaInstitute
dwellers that are characterized by a distinctive of Marine Science, Gloucester Point, VA
brushoflong,thicklypackedsetaearrangedin (VIMS). VIMS numbers listed refer to field
transverseparallelrowsontheextensorsurface specimen numbers. Measurements correspond
of dactyl of the smaller first chela (Coutie`re, to carapace length (CL) in millimeters, taken
1908,1909). Thedistinctivesetalbrush isused fromthemostposterioredgeofthecarapaceon
tocollectfoodfromthesurfacesofthesponge the dorsal midline to the base of the rostrum.
canalsinwhichtheylive(Duffy,2003). Specimens were figured using a camera lucida
Collections of West Atlantic Synalpheus on a Wild M3C dissecting microscope or
duringthelast15 yearshaverevealedacomplex from digital photos taken by a Diagnostic
ofmorphologicallysimilarspeciesintheGam- Instruments Spot RT photo system using an
barelloides group that includes Synalpheus OlympusBX50lightmicroscope.
brooksi Coutie`re, 1909, Synalpheus bousfieldi
Chace, 1972, Synalpheus chacei Duffy, 1998,
ORDERDECAPODALATREILLE,1802
and two additional species described here.
Synalpheus brooksi is predominantly found FAMILYALPHEIDAERAFINESQUE,1815
in two common shallow-water sponges,
GENUSSYNALPHEUSBATE,1888
Spheciospongia vesparium Lamark, 1814 and
LissodendoryxcolombiensisZeaandvanSoest, Synalpheus carpenteri, new species
1986,butithasalsobeencollectedinfrequently figures 1–7
fromavarietyofothersponges(personalobs.;
Macdonald et al., 2005). In 1972, Chace
Synalpheus bousfieldi (in part), in Dardeau 1984:
describedacloselyrelatedspecies,S.bousfieldi,
USNM 189150,fig.10.
that inhabits a wide diversity of sponges
Synalpheus‘‘bousfieldiA’’,inMorrisonetal.,2004,
throughout the Caribbean (Chace, 1972;
and inMacdonald et al.,2005.
Dardeau, 1984; Macdonald et al., 2005). Both
-
species have been considered highly variable HOLOTYPE: (USNM 1092295, original
morphologically,butrecentworkindicatesthat VIMS 04CBC4201), Long Reef, Belize, from
much of this variation is attributable to canals of Agelas clathrodes Schmidt, 1870.
distinct, morphologically cryptic species, in- Carapace length (CL): 3.32 mm.
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cludingS.chaceiandthetwonewspeciesinthe ALLOTYPE: (USNM 1092296, original
brooksicomplexdescribedherein. VIMS 04CBC4202), Long Reef, Belize, from
canals of same individual A. clathrodes as
holotype. CL: 3.86 mm.
MATERIALS AND METHODS
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PARATYPES: (AMNH Crustacea 18492,
Specimens were collected between 1988 and original VIMS 04CBC4203), Long Reef,
2004fromspongesinthevicinityofCarrieBow Belize, from canals of same individual A.
-
Cay on the Belize Barrier Reef, Central clathrodes as holotype. CL: 3.01 mm.
America (16u489N, 88u059W), the San Blas (AMNH Crustacea 18493, original VIMS
Islands on the Caribbean coast of Panama´ 04CBC4305), Long Reef, Belize, from canals
(9u349N, 78u589W), and the Exuma Islands of of A. clathrodes. CL: 2.74 mm.
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theBahamas(23u469N,76u069W).Mostshrimp ADDITIONAL SPECIMENS EXAMINED: ,
werecollectedalivefromtheir hostspongesby (USNM 1092297, 1092298, original VIMS
2006 MACDONALD AND DUFFY: SPONGE-DWELLING SNAPPING SHRIMP 3
96CBC3303-3304), Carrie Bow Cay, Belize, ner,withlongerventrolateralspine,notreach-
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from canals of A. clathrodes. (VIMS ing third segment of antennular peduncle.
98CBC0601),CurlewReef,Belize,fromcanals Scaphocerite blade absent, acute lateral spine
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of A. clathrodes. (VIMS 98CBC3103), robust, with lateral margin slightly concave,
Carrie Bow Cay, Belize, from canals of slightly surpassing basicerite spine, not reach-
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Agelas dispar. (VIMS 98CBC3301), Carrie ing third segment of antennular peduncle;
BowCay,Belize,fromcanalsofA.clathrodes. mesial projection at base of scaphocerite
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2 , (VIMS 01LS0101, 0105-06), White present. Third maxilliped (fig. 2) with distal
Horse Rocks, Exuma Islands, Bahamas, from circlet of spines on distal segment, without
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canals of A. clathrodes. 3 , 5 (USNM ventrodistal spine on antepenultimate seg-
1092299-1092306, original VIMS 01LS1301- ment. Remaining mouthparts as figured
1307,1309),G-spot,ExumaIslands,Bahamas, (fig. 2).
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from canals of A. clathrodes. , (VIMS Major first pereopod (fig. 3) massive, fin-
01LS1501-02), G-spot, Exuma Islands, gers clearly shorter than half length of palm;
Bahamas, from canals of A. clathrodes. fixed finger slightly shorter than dactyl. Palm
Specimens examined and provisionally as- of chela with distal superior margin pro-
signed to S. carpenteri. These individuals will tuberance, which is secondarily produced
-
herein be referred to as S. cf. carpenteri. : 5 distally, directed slightly downward, toward
individuals (VIMS 93P1106), Aguadargana dactyl.
Reef, San Blas Islands, Panama, from canals Minor first pereopod (fig. 3) with palm
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of A. clathrodes. , 2 (VIMS 93P2609-10), clearly less than two times longer than high;
Limones Reef, San Blas Islands, Panama, fingers clearly shorter than palm; dactyl with
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from canals of A. clathrodes. , (VIMS flexor margin concave, bladelike, with 2
93P4703), Limones Reef, San Blas Islands, distinct distal teeth, subequal in length; trans-
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Panama, from canals of A. clathrodes. verse dorsal setal combs on dactyl, very
(VIMS 93P5306), Aguadargana Reef, San conspicuous; fixed finger with flexor margin
Blas Islands, Panama, from canals of A. straight, bladelike, and 2 distinct teeth sub-
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clathrodes. 2 , (USNM 1092307-109309, equal in length.
original VIMS 92P6101-03), San Blas Islands, Second pereopod (fig. 4) with carpus 5-
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Panama, from canals of A. clathrodes. , segmented, subequal in length to merus. Both
(USNM 1092310-1092311, original VIMS fingersterminating ina narrow,curved tooth.
92P6903-04), Mamitupo Reef, San Blas Third pereopod (fig. 4) slender; dactyl
Islands,Panama,fromcanalsofA.clathrodes. biunguiculate,withflexorunguisclearlythick-
DESCRIPTION: Body form subcylindrical; er than extensor, mesial margin of flexor
carapace smooth, sparsely setose, with pter- unguis strongly convex; propodus with row
ygostomian corner produced into bluntly of 6 movable spines on flexor margin and one
acute angle, posterior margin with cardiac pair of distal movable spines flanking base of
notch distinct. Rostrum longer than orbital dactylus; carpus with distal movable spine on
hood (fig. 1), distinctly narrower, distally flexor margin; merus almost 4 times longer
upturned; margins in dorsal view, straight. than wide, without movable spines on flexor
Orbitorostral process absent. Ocular hoods margin; mesial lamella on coxa present.
dorsally convex; in dorsal view, bluntly acute, Fourth pereopod (fig. 4) similar to third,
separated from rostrum by deep adrostral slightlyweaker.Fifthpereopod(fig. 4)weaker
sinus. Ocular process triangular, flanged than fourth; propodus with only 3 spines on
posteriorly onto lower side of eye. Ocellary flexormargin,and4transversecombsofstout
beak in lateral view not rodlike, broader at setae on ventral face; carpus without distal
base. Stylocerite acute, with blunt tip; mesial spine.
margin concave; reaching midpoint of first First pleura (fig. 1) of male with posterior
segment of antennular peduncle. First anten- corner distinctly produced ventrally into
nular segment without ventromesial tooth, small, anteriorly directed hook; second pleura
and with two basal ventral processes. of male broadly rounded; third to fifth pleura
Basicerite without spine on dorsomesial cor- of male progressively acute, but not pointed.
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Fig. 1. Synalpheus carpenteri, new species. Holotype 3.32 mm (USNM 1092295, VIMS04CBC4201)
fromAgelasclathrodes,LongReef,Belize:A,anteriorregionofcarapaceandcephalicappendages,dorsal
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view; B, same, lateral view; C, telson and left uropods, dorsal view; D, abdomen, lateral view. Allotype
3.86 mm(USNM1092296,VIMS04CBC4202)fromA.clathrodes,LongReef,Belize:E,anteriorregionof
-
carapaceandcephalicappendages,lateralview;F,telson,dorsalview;G,abdomen,lateralview. 3.59 mm
(VIMS96CBC3304)fromA.clathrodes,CarrieBowCay,Belize:H,anteriorregionofcarapaceandcephalic
appendages,dorsalview.Scale bar51 mm for A,B, C,E, F, H; 1.6mm for D; 2.5mm for G.
First pleopod (fig. 5) of male with 2 Telson (fig. 1) length three-quarters width
terminal setae on endopod; second pleopod of proximal margin; marginal convex lobe
of male with marginal setae on exopod present; posterior corners adjacent to spines
originating in distal two-thirds; appendix obtuse. Anal flaps, perianal setae, and post-
interna present on second to fifth male analsetalbrushabsent.Uropodswithasingle
pleopods. Second pleopod (fig. 5) of female fixed tooth on outer margin of exopod
with marginal setae on exopod originating in distinctly removed from the movable one,
distal one-third; appendix interna present on thelatterslightlylongerandmoreslenderthan
second to fifth male pleopods. adjacent inner fixed tooth.
2006 MACDONALD AND DUFFY: SPONGE-DWELLING SNAPPING SHRIMP 5
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Fig. 2. Synalpheus carpenteri, new species. 3.59 mm (USNM 1092298, VIMS 96CBC3304) from
Agelasclathrodes,CarrieBowCay,Belize:A,mandible;B,firstmaxilla,inpart;C,secondmaxilla;D,first
maxilliped;E,secondmaxilliped;F,thirdmaxilliped;G,same,detailofdistalregion.Scalebar51 mmfor
C,D,E, F; 0.5 mm for A;0.25 mm forB, G.
COLOR IN LIFE: Faint to bright orange subquadrate; telson length/proximal margin
overall,colordistinctlymoreintenseinfingers width averages 0.77 (range 5 0.67–0.88, N 5
and distal palm of major chela. Ovaries and 6). The lengths of the lateral spines of the
developing embryos are brilliant orange. scaphocerite and basicerite also vary. In most
ETYMOLOGY: We have named this species individuals, both spines are very short, ex-
after Michael Carpenter, Caribbean Coral tendingtothemidpointofthesecondsegment
Reef Ecosystem program, National Museum of antennular peduncle, while in some indi-
of Natural History, Smithsonian Institution, viduals both spines extend almost to the third
without whose assistance and camaraderie segment of the antennular peduncle. There is
over many years the work herein would have alsovariationintheshapeoftheprotuberance
been impossible. on the palm of the major chela. In some
VARIATION: The shape of the telson varies individuals, the protuberance appears round-
from very broad and almost triangular to ed and is barely secondarily produced distally
6 AMERICAN MUSEUMNOVITATES NO. 3543
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Fig.3. Synalpheuscarpenteri,newspecies.Holotype 3.32 mm(USNM1092295,VIMS04CBC4201)
fromAgelasclathrodes,LongReef,Belize:A,chelaofmajorfirstpereopodinlateralview;B,same,anterior
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regioninlateralview;C,same,dorsalview.Allotype 3.86 mm(USNM1092296,VIMS04CBC4202)from
-
A. clathrodes, Long Reef, Belize: D, anterior region of chela of major first pereopod in lateral view.
3.59 mm (USNM 1092298, VIMS 96CBC3304) from A. clathrodes, Carrie Bow Cay, Belize: E, anterior
-
regionofchelaofmajorfirstpereopodinlateralview.Paratype 2.74mm(AMNHCrustaceaxxx,VIMS
04CBC4305)fromAgelasclathrodes,LongReef,Belize:F,anteriorregionofchelaofmajorfirstpereopod
in lateral view; G, minor first pereopod, setae removed, lateral view; H, same, anterior region, with setae;
I,same,detailofdistaltipsoffingers,reverseview.Scalebar51mmforB,C,D,E,F,G,H;2.5 mmforA;
0.52 mm forI.
(figs. 3F, 6C, F), while in others the distal is typically found in this species, although not
portionisstronglyproduced,becomingstrong- entirely rare. The rostrum of most individuals
ly acute distally (fig. 3B, D, E). Finally, the (see figs. 1H, 6A, B) is subequal to or slightly
rostrumoftheholotype(fig. 1A)islongerthan longerthan theorbitalhoods.
2006 MACDONALD AND DUFFY: SPONGE-DWELLING SNAPPING SHRIMP 7
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Fig. 4. Synalpheus carpenteri, new species. 3.59 mm (USNM 1092298, VIMS 96CBC3304) from
Agelas clathrodes, Carrie Bow Cay, Belize: A, third pereopod; B, same, detail of distal region; C, fourth
pereopod; D, same, detail of distal region; E, fifth pereopod; F, same, detail of distal region; G, second
pereopod;H,same,detailofdistalregion.Scalebar51 mmforA,C,E,G;0.25mmforB,D,F;0.5 mm
forH.
HOSTS AND ECOLOGY: Synalpheus carpen- Synalpheus agelas Pequegnat and Heard,
teri,n.sp.isahostspecialist,foundonlyinthe 1979.
canals of the common Caribbean sponges DISTRIBUTION: BelizeBarrierReef;SanBlas
Agelas clathrodes and Agelas dispar. It is Islands,Panama;ExumaIslands,Bahamas.
found in approximately equal sex ratios, and REMARKS: S. carpenteri is one member of
individualspongescancontainasinglepairto a complex of closely related, morphologically
severaltensofshrimp.Synalpheuscarpenteriis similar Synalpheus species that includes S.
often found together in the host sponge with brooksi, S. bousfieldi, and S. chacei. It is most
the closely related eusocial S. chacei and/or similar morphologically to S. bousfieldi. The
8 AMERICAN MUSEUMNOVITATES NO. 3543
S. bousfieldi. Telson length/proximal margin
width ratios range from 0.67 to 0.88 in S.
carpenteri (N5 6)and from 1.01 to1.25 inS.
bousfieldi (N 5 13). Additionally, the lateral
spines of the basicerite and scaphocerite
barely,ifever, reachbeyondthe distal margin
of the second segment of the antennular
peduncle, while in all other members of the
species complex, both spines typically reach
a least beyond the midpoint of the third
segment, and often past the distal margin of
the third segment (see figs. 14 and 15, as well
as Chace’s [1972: 87, fig. 29] figure of the
holotype and paratype of S. bousfieldi). It is
likely that some of the specimens collected
from Agelas dispar Duchassaing and Miche-
lotti, 1864 examined by Dardeau (1984: fig.
10)andassignedtoS.bousfieldiareactuallyS.
carpenteri. We have occasionally found speci-
mens that we consider to be S. bousfieldi
inhabiting Agelas sp., but they are easily
distinguishable from S. carpenteri in their
overalldullcolor,narrowtelson,andrelative-
ly long basicerite and scaphocerite lateral
spines (personal obs.; fig. 17A–C). Specimens
collected from Agelas clathrodes in the San
Blas Islands of Panama (fig. 9) are provision-
ally assigned to S. carpenteri. While these
specimens share the orange coloration and
short lateral spines of the basicerite and
scaphocerite, telson widths vary, and they
are rarely as wide as in S. carpenteri individ-
uals found in Belize or the Bahamas.
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Fig. 5. Synalpheus carpenteri, new species.
Synalpheus ruetzleri, new species
3.59 mm (USNM 1092298, VIMS 96CBC3304)
figures 8–13
from Agelas clathrodes, Carrie Bow Cay, Belize:
A, first pleopod; B, second pleopod. Paratype
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3.01 mm (AMNH Crustacea 18492, VIMS Synalpheus ‘‘bousfieldi blade’’, in Morrison et al.,
04CBC4203) from A. clathrodes, Long Reef, 2004, and inMacdonald etal., 2005.
Belize: C, first pleopod; D, second pleopod. Scale
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bar51 mm. HOLOTYPE: (USNM 1092312, original
VIMS 01CBC4502), Sand Bores, Belize, from
most obvious identifying character of S. canalsofthebluecrypticspongeHymeniacidon
carpenteriisitscolorinlife.Noothermember cf.caeruleaPulitzer-Finali,1986.CL:3.59 mm.
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of the S. brooksi species complex shares the ALLOTYPE: (USNM 1092313, original
overall orange coloration of this species, or VIMS 01CBC4501), Sand Bores, Belize, from
especially the brilliant orange of the ovaries canalsofthesameindividualH.cf.caeruleaas
and developing embryos. While there is holotype. CL: 4.06 mm.
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variation in both the relative width of the PARATYPES: (USNM 1092314, original
telson and the relative lengths of the lateral VIMS 01CBC6101), Sand Bores, Belize, from
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spinesofthebasiceriteandscaphocerite,there canals of H. cf. caerulea. CL: 3.13 mm.
is little or no overlap in these characters with (USNM1092315,originalVIMS01CBC5601),
2006 MACDONALD AND DUFFY: SPONGE-DWELLING SNAPPING SHRIMP 9
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Fig.6. Synalpheuscarpenteri,newspecies. 3.32 mm(USNM1092302,VIMS01LS1304)fromAgelas
clathrodes, G-spot, Exuma Islands, Bahamas: A, anterior region of carapace and cephalic appendages,
-
dorsal view; B, telson, dorsal view; C, anterior region of chela of major first pereopod, lateral view.
3.36mm (USNM 1092299, VIMS 01LS1301) from A. clathrodes, G-spot, Exuma Islands, Bahamas:
D, anterior region of carapace and cephalic appendages, dorsal view; E, telson, dorsal view; F, anterior
regionof chelaof majorfirst pereopod, lateralview.Scale bar51 mm.
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Sand Bores, Belize, from canals of H. cf. from canals of H. cf. caerulea. , (VIMS
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caerulea. CL: 3.51 mm. (USNM 1092316, 93CBC1102-03), Blue Ground Range, Belize,
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original VIMS 01CBC5602), Sand Bores, from canals of H. cf. caerulea. (VIMS
Belize, from canals of H. cf. caerulea. CL: 01CBC1301), Blue Ground Range, Belize,
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3.20 mm. (AMNHCrustacea18494,original from canals of H. cf. caerulea. (VIMS
VIMS 01CBC6301), Sand Bores, Belize, from 93P3803), Wichubhuala Reef, San Blas
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canals of H. cf. caerulea. CL: 4.43 mm. Islands,Panama,fromcanalsofH.cf.caerulea.
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(AMNH Crustacea 18495, original VIMS (USNM 1092317, original VIMS 91P4902),
01CBC6302), Sand Bores, Belize, from canals Guigalatupo Reef, San Blas Islands, Panama,
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ofH.cf.caerulea.CL:3.99 mm. from canals of an unidentified sponge.
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ADDITIONAL SPECIMENS EXAMINED: , (VIMS 91P4101), Porvenir Reef, San Blas
(VIMS 01CBC4601-02), Sand Bores, Belize, Islands, Panama, from canals of an unidenti-
10 AMERICAN MUSEUMNOVITATES NO. 3543
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Fig.7. Synalpheuscf.carpenteri,newspecies. 3.32mm(USNM1092309,VIMS92P6103)fromAgelas
clathrodes,SanBlasIsland,Panama:A,anteriorregionofcarapaceandcephalicappendages,dorsalview;
-
B,telson,dorsalview;C,anteriorregionofchelaofmajorfirstpereopod,lateralview. 2.14 mm(USNM
1092308,VIMS92P6102)fromA.clathrodes,SanBlasIsland,Panama:D,anteriorregionofcarapaceand
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cephalic appendages, dorsal view; E, telson, dorsal view. 2.49 mm (USNM 1092311, VIMS 92P6904):
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F,telson,dorsalview. 2.26 mm(USNM1092310,VIMS92P6903)fromA.clathrodes,MamitupoReef,
SanBlas Islands, Panama: G,telson, dorsalview.Scale bar51 mm.
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fied orange tube sponge. (VIMS 91P0703), dorsally convex; in dorsal view, bluntly acute,
Ulagsukun Reef, San Blas Islands, Panama, separated from rostrum by deep adrostral
fromcanalsofanunidentifiedsponge. sinus. Ocular process triangular, flanged
DESCRIPTION: Body form subcylindrical; posteriorly onto lower side of eye. Ocellary
carapace smooth, sparsely setose, with pter- beak in lateral view not rodlike, broader at
ygostomian corner produced into bluntly base. Stylocerite acute, with blunt tip; mesial
acuteangle,andposteriormarginwithcardiac margin concave, surpassing midpoint of first
notch distinct. Rostrum (fig. 8) longer than segment of antennular peduncle; this segment
orbital teeth, and slightly narrower, distally without ventromesial tooth, with two basal
upturned; margins in dorsal view, straight. ventral processes. Basicerite without spine on
Orbitorostral process absent. Ocular hoods dorsomesial corner, with longer lateral spine,