Erylus toxiformis (Porifera, Geodiidae), a new species from the southwestern Atlantic

5 Pages·1999·2.6 MB·English

by  Mothes, Beatriz

Beaufortia
INSTITUTE FOR SYSTEMATICS AND POPULATIONBIOLOGY
(ZOOLOGICAL MUSEUM) UNIVERSITYOF AMSTERDAM
Vol. 49, no.4 October5, 1999
Erylus toxiformis (Porifera, Geodiidae),anew species from the
southwestern Atlantic.
BeatrizMothes'& CléaLerner
*Museude CienciasNaturais, Fundaçâo doRioGrandedoSul
Cx. Postal1188,90690-000,PortoAlegre,RS, Brazil.
E-mail:[email protected]
**Departamento deZoología, InstitutodeBiociências, UniversidadedeSaPaulo&
MuseudeCienciasNaturais,Fundaçâo £'oobotânicadoRioGrandedoSul
Cx. Postal 1188,90690-000,PortoAlegre,RS, Brazil.
E-mail:[email protected]
Keywords: Porifera, Demospongiae,Geodiidae,Erylus toxiformis n.sp.,southwestern Atlantic, taxonomy.
Abstract
Anewspecies ofErylus (Porifera, Geodiidae)fromthe southwestern Atlantic,Erylus toxiformis n.sp. is described
offRio Grande doSulcoast,Brazil.
INTRODUCTION 1934 (43-165 m), E. diminutus Mothes et al.,
1999 (183 m), and Erylus sp. (Mothes &
Erylus Gray, 1867is a genus with Tethyan distri- Umpierre, in prep.). In the course of dredging
bution restricted to tropical and subtropical operations off the coastofRio Grande do Sul, a
areas (Van Soest, 1994). A brief history of the new species ofErylus was identified from the
genusis provided in Motheset al. (1999). slope (31°05°S 49°31°W), at a depth of 300 m
Erylus is represented on the Brazilian coast (Fig. 1). In addition to its description below, a
by the following species (Mothes etal., 1999): E. key to the species ofErylus from the Brazilian
formosus Solías, 1886(3-72 m), E. corneus Boury- coast is given. Threeofthose species are "ende-
Esnault, 1973 (45 m), E. alleni De Laubenfels, mics" (E. corneus, E. diminutusand the new spe-
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Abbreviations forinstitutions used inthe textare:
BMNH: Natural HistoryMuseum,London.
FURG: Fundaçâo Universidade doRio Grande,
RioGrande, Brazil.
FZB: FundaçâoZoobotânica do Rio Grandedo
Sul, Porto Alegre,Brazil.
MCN: Museu de Ciencias Naturais, PortoAle-
gre,Brazil.
MCN-POR: MCN,Poriferacollection.
ZBM: Museum fur Naturkunde der Humboldt-
UniversitatzuBerlin,Berlin.
SYSTEMATICS
OrderAstrophorida Lévi, 1973
Family GeodiidaeGray, 1867
GenusErylus Gray, 1867
Type species Stelletta mamillaris Schmidt, 1862:48,
Pl. V, Fig. 1, by original designation and mono-
typy.
Diagnosis: Geodiidaewithectosomal microrhabds
and aspidasters or sterrasters with the following
forms: eliptical to disc-shaped, flattened to glo-
bose, irregular (with lobes) orregular outlineand
Fig. 1. Map ofthe study arealocation where the sample microspined to smooth surface. Incurrent chan-
was collected. nels are uniporal; oscules are large openings
(Mothes etal., 1999).
cies) and two are known also from the West In-
dies(E. formosusand E. alleni).
Erylus toxiformis n.sp.
MATERIALSAND METHODS (Figs. 2-11)
The studied sample was dredged by the R/V Type material: HOLOTYPE- Museu de Ciências
Atlántico Sul during the years 1986 to 1988by Naturais, MCN-POR 1599, off Rio Grande do
"Projeto Talude" of the Fundaçâo Universidade Sul coast, 31°05°S 49°31°W, Brazil, slope, 300
de Rio Grande(FURG). It is deposited in the m, November 1988, R/V Adântico Sul (FURG)
Porifera collection ofthe Museu de Ciencias Na- coll.
turais ofFundaçâo Zoobotânicado Rio Grande
do Sul,Brazil. Description (Figs.2-3): Amorphous fragment (2 x 1
Skeletal slides and dissociated spicule mounts x 0.5 cm). Surface smooth, slightly microhispid
were made following Mothes (1996). The SEM becauseofprotruding spicules; withnarrowecto-
study was madeusing aJeolJSM-5200 Scanning chones which seem to traverse the cortex; one
Microscope. Scales for SEMpictures are indicat- oscule observed, circular, 1 mm in diameter;
ed with each spicule. Measurements of spicule ostia 0.5 mm in diameterwith distance between
referto minimum-mean-maximumin(j.m. them from 1 to 4mm, distributedon the surface,
Preliminary results of this materialwere pub- except around the oscule. Colour ofpreserved
lishedin the "Bookof Abstracts" of "VI Congre- material: externally white and internally grey;
so Latinoamericano de Ciencias del Mar (CO- consistency is externally hard and internally
LACMAR), Mar del Plata, Argentina". compressible.
30
Fig. 4. Erylus toxiformis n.sp.,holotype MCN-POR 1599,
perpendicular sectionofskeleton. Scale= 100µm
Figs. 2-3. Erylus toxiformis n.sp., holotype MCN-POR 1599,
preserved material, offRio Grande do Sul State coast Microscleres: Sterraster-like aspidasters
(31°05°S49°31°W), Brazil, 2. general view, 3.surface
(Figs.5-8) disc-shaped to slightly eliptical and not
detail. Scale=0.2 cm.
flattened, hilum situated on one side, surface
madeup ofdense groupsof polygonal, randomly
Skeleton (Fig. 4): Ectosome: theusual detach- distributed microspines, 207.0-577.5-506.0 x
able cortex, 0.5 mm thick, a layer packed with 184.0-255.7-414.0pm; microstrongyles (Fig.9)
tangentially placed sterrasters 0.4mm and a thin smooth, centrotylote, slighdy curved, 50.6-71.4-
discontinuous ectochrote packed with micro- 96.6 x 2.3-5.5-6.9 pm; oxyasters (Figs. 10-11)
strongyles. Choanosome: radial architecture with 3 to 8 smooth rays and with a diameterof
comprised oforthotriaenes whose cladomes 34.5-70.6'-96.6 pm; reduced forms diactines,
touch the lower layers ofthe sterrasters. Some- resembling toxas, but are much longer than
times oxeas cross the cortex and protrude at the proper oxyasters,: 73.6-59.5-103.5pm.
sponge surface; oxyasters, a reduced numberof Substrate:mudandsilt.
sterrasters and rare microstrongyles are random- Etymology: the name refers to the morphology
ly distributed. ofreduced oxyasters thatare similar to toxas.
Megascleres: Calthrops-like orthotriaenes
(Fig. 12) with clads and rhabdalmost isoactine, REMARKS
cladome 361.0-636.5 and rhabdome 199.5-
389.5 x 11.5-23.0 |am; oxeas (Fig. 13) straight, The new species differs from other species of
sometimes slightly curved, mucronate or blunt, Erylus registered for the West Indies and Brazi-
rarely strongylote, 897.0-757(9.6'-1817.0x 9.2- lian coast by the presence of reduced oxyasters
17.3-25.3|xm. similar to toxasandby sterraster-like aspidasters.
31
32
Figs.5-13. Erylustoxiformisn.sp.,holotypeMCN-POR 1599, Fundaçâo de Amparo à Pesquisa do Estado de
5.aspidaster showingthehilumin the centre,6. aspidaster, Sào Paulo (FAPESP, Brazil, Proc. 96/11786-8).
7. aspidaster, surface detail, 8. young aspidaster, 9.smooth Fundaçâo de Amparo à Pesquisa do Estado do
microstrongyle, 10. oxyasters with smooth rays, 11. toxa-
Rio Grande do Sul (FAPERGS, Brazil, Proc.
likereducedformsofoxyasters, 12. calthrops-like orthothri-
aene, 13.oxea. 95/0728.3) providing supportto B. Mothes.
REFERENCES
KEY TO THE SPECIES OF ERYLUSFROM BOURY-ESNAULT,N., 1973. Campagne de la Calypso
THEBRAZILIAN COAST aularge des côtes atlantiques de l'Amérique du Sud
(1961-1962). I, 29. Spongiaires. Rés. Sci. Camp.
Calypso, 10:263-295.
1. Orthotriaeneswithoxeas 2
Dichotriaeneswith short rhabdwithstrongyles varying GRAY,J.E., 1867. Notes onthe arrangements ofsponges,
tostrongyloxeas, flattenedaspidasterswith slightlyirreg- with the description ofsome new genera. Proc. Zool.
Soc. London, 1867:492-558.
ularoutline E.diminutus
LAUBENFELS,M.W. DE, 1934. New sponges from the
Puerto Rican deep. Smithsonian Miscllaneous
2. Atypical aspidasters, sterraster-like disc-shapedand not
,
Collections, 91 (17): 1-28.
flattened,reducedtoxas-likeoxyaster
LEVI, C., 1973. Systématique de la classedes Demo-spon-
Ej . toxiformisn.sp.
Typical Aspidasters 3 giaria (Démosponges). pp. 577-631. In: Brien, P., C.
Lévi, M. Sará, O. Tuzet, &J. Vacelet: Spongiaires.
Traité de zoologie; anatomie, systématique, biologie
3. Eliptical flattenedaspidasters 4
(Grassé,P.-P., éd.).Paris, Masson, vol.3,fase.1.
Finger-shaped aspidasters E. formosus
MOTHES,B., 1996. Esponjas da PlataformaContinental
4. One categoryofoxyasters E.corneus Norte e Nordeste do Brasil (Porifera, Demospongiae).
PhD Thesis, Universidade de Sào Paulo,Sào Paulo: 1-
Twocategories ofoxyasters E.alleni
233.
SCHMIDT, O., 1862.Die Spongien des Adriatischen
ACKNOWLEDGEMENTS
Meeres. Leipzig, Engelmann:i-viii, 1-88.
SOEST, R.W.M.VAN, 1994. Demospongedistribution
Theauthors are grateful to Dr. Rob van Soest, patterns, pp. 213-223. In: Soest, R.W.M. van, T.M.G.
Instituut voor Systematiek en Populatiebiologie vanKempen,&J.C.Braekman,(eds): SpongesinTime
(Zoôlogisch Museum), Amsterdamforexamining and Space. Balkema,Rotterdam.
SOLLAS,W.J., 1886. Preliminary account ofthe tetracti-
thematerialandfor revising the manuscript, and
nellid sponges dredged by HMS "Challenger" during
to Dr. Ricardo R. Capitoli, Fundaçâo Universi- the years 1873-76. Part I.The Choristida. Sci. Proc.R.
dadedoRio Grande, Brazil forsending the spec- DublinSoc., 5: 177-199.
imen forstudy. C. Lerneris aPhD studentat the
University ofSào Paulo with a scholarship from Received: August 29, 1998
33