More North Jamaican deep fore-reef sponges

29 Pages·1999·7.7 MB·English

by  Lehnert, Helmut

Beaufortia
INSTITUTE FOR SYSTEMATICSANDPOPULATIONBIOLOGY
(ZOOLOGICAL MUSEUM) UNIVERSITY OF AMSTERDAM
Vol. 49, no. 12 December 28,
More NorthJamaican deepfore-reef sponges
Helmut Lehnert& Rob W.M. van Soest
*) Institute&Museumfor Geology andPaleontology, Goldschmidtstr. 3,37077 Gôttingen, Germany
Presentaddress: Institutefor Organic Chemistry, Butenandtstrasse5-13,HausF,81377
Miinchen-Grosshadern, Germany
**) Institutefor Systematics andPopulation Biology (Zoological Museum),
University ofAmsterdam, P.O. Box 94766, 1090GTAmsterdam, TheNetherlands
Abstract
A second investigation ofthe North Jamaicandeep fore-reef slope,usingmixed gastoreach depthsfrom 70m toamaxi-
mum of 107 mdepth,revealed 43 species,9 ofwhich arenewto science: Erylus incrustans, Polymastiafordei,Pseudaxinella
flava Phakellia bettinae,Iotrochota agglomerata,Callyspongiadensasclera,Niphateslutea,Xestospongiadeweerdtae, andEuryspongia
,
lankesteri.
INTRODUCTION The most westward locality visited was
PinnacleII,aprominent reef structure exactly in
The high proportion of new sponge species dis- front of the Discovery Bay Marine Laboratory.
covered by mixed gas dives to the deep fore-reef The area investigated extended eastward to a
ofJamaica (Lehnert & Van Soest, 1996) initiated locality called Dairy Bull, roughly 5 km distance
a second enterprise to investigate the sponge from PinnacleII.
fauna of this habitat more closely. In June and
July 1996,ninemixedgas divesto depths from70
to 107 mwitha totalbottom timeof 180minutes METHODS
(and atotal dive-time of 1107min) were carried
out in different localities in the Discovery Bay Sponges or fragments of them were sampled
area on the north coast of Jamaica. Here we after being photographed in situ. Specimens
report new materialcollected during these dives, were then fixed in a glutaradehyde/cacody-
including 9 species newto science. late/seawatersolution for24- 48 hoursand after
141
rinsing in seawater transferredin several steps to ter; small oxyasters (Fig. 8): 12-16(am indiameter;
70% ethanol. Some samples were fixed in a slightly centrotylote, smooth microxeas (Fig. 3):
formaldehyde/ethanol/seawater solution. From 45-68 x2-3 f^m.
large specimens onlyparthas beenfixed, the rest Remarks: Spicule types and dimensions of all
was dried.Diving andidentificationfollowedpro- known West-Indian species of Erylus are given in
cedures already described previously (Lehnert & Table 1.Our specimen resemblesE. ministrongylus
Van Soest, 1996, 1998).Most material is deposit- Hechtel in many spicular characters, but differs
ed in the Zoological Museum, Amsterdam in its encrusting growth form, in the grey-green
(ZMA), some additionalspecimens arekept in the colour, in having larger oxeas and in aster-mor-
Institute & Museum for Geology and Paleonto- phology. Hechtel (1965) described his specimen
logy, Gôttingen. as being hemispherical, yellow or pale orange in
colour, and the surface covered by low tubercles.
A recent review ofErylus from Brazil (Mothes
SYSTEMATICS & Lerner, 1999) didnot showany species close to
our new species among the five recorded from
Theorderinwhichthespecies are treatedfollows thatarea.
Lehnert& Van Soest, 1998
Order Lithistida
Class Demospongiae Family Theonellidae
Order Astrophorida GenusDiscodermiaDu Bocage, 1869
Family GeodiidaeGray, 1867
GenusErylus Gray, 1867 Discodermiasp.
Erylus incrustans sp.n. Discodermia dissoluta sensu Lehnert & Van Soest,
Figs. 1-8 1996: 55, figs. 2, 39-42 (not: Schmidt, 1880)
Material: Holotype ZMA POR. 13510, Material: ZMA POR. 13518, Discovery Bay,
Discovery Bay, Dairy Bull, 70.1 m, 27. 6. 1996, LTS, 85 m, 20. 6. 96, #J96/17-1,2; ZMAPOR.
#J96/37-l 13519, Discovery Bay, LTS, 73 m, 20. 6. 96,
#J96/20; ZMA POR. 13520, Discovery Bay,
Description: Dark, grey-green, thinly, encrusting LTS, 82-91 m, 21. 6. 96, #J96/26-l,2,3,4,5;
sponge (Fig. 7), 2 - 3 mm in thickness, lateral ZMA POR. 13521, Discovery Bay, LTS, 85 m,
expansion up to 8 cm in diameter, overgrowing #J96/32-l,2; ZMAPOR. 13522, Discovery Bay,
the skeleton of a dead Ceratoporella nicholsoni. MI, 82 m, #J96/34; ZMA POR. 13523,
Surfacesmooth. Numerouspores(<0.1 mm)and Discovery Bay, Dairy Bull, 79 m, #J96/36-l,2;
several slightly elevated roundoscules, 2-3 mm ZMAPOR. 13524, Discovery Bay, Dairy Bull,79
0, scattered over the surface. A large quantity of m, #J96/38-l,2; ZMA POR. 13525+13538,
the sponge is nestling in bore-holes in the Discovery Bay, Dairy Bull, 79 m, 28. 6.96,
Ceratoporella skeleton. #J96/47-1,2; ZMAPOR. 13526, Discovery Bay,
Skeleton:There is a thick (1 mm) cortex of crowd- LTS, 107 m, 4. 7. 96, #J96/50; ZMA POR.
ed aspidasters andbelowa thinveneerof sponge 13527, Discovery Bay, Pinnacle II, 79-85 m,
tissue withmega-andmicroscleres. #J96/56-l,3,4.
Spicules: Relatively smallandrare triaenes(Fig. 2),
with rhabds: 152-163 x 14-16 |am, cladi: 180 - Description: Hard, conical, greyish whiteto yellow-
320 |am; oxeas or stylotes (Fig. 1):560-1080x 20 brown sponges, 1.3-6 cm high and 0.5-5.5 cm in
-38 jam; very thick aspidasters (Figs 1,4,5), surface diameter.One or several apical oscules, an apical
sometimeswith one or several knobby elevations depression develops upon drying. Some speci-
or occasionally with a shallow, circular depres- mens were growing on other sponges (Topsentia
sion: 96-192 x 72-83 x 52-56 pn; tylasters (Figs ophirhaphidites, Ceratoporella nicholsoni), some were
6,8) with microspined rays: 32-35 jim in diame- partially overgrown by sponges (Agelas spp.,
142
Figs. 1-8:Erylus incrustans sp.n.,(all SEMexcept7) 1.overview ofspicules includingoxeasandaspidasters, 2. megascleres
includingatriaene, 3.centrotylote smoothmicroxea, 4. full-grown aspidaster, 5.incipientaspidaster, 6. tylaster, 7. holotype
photographedinsitu before collection (scale = 1 cm), 8.oxyaster (smalleraster) and tylaster.
143
72-83
2-3
orthotriaenes x
x
incrustans n. 560-1080 152-163 14-16 180-320 96-192 45x-68 tylaster 32-35 oxyaster12-16
thin
sp.
x
x x
30-58x1-3
transiens Weltner, 1882 700-2000 10-35 ortho 150-500 10-30 100-400 100-190 60-100 oxyaster7-28
x
Laubenfels, calthrops-like 270xl2/ray 40-50 chi-/tylasters
12 oxyeuaster
trisphaerus x 2 ———'
de 1953 900x 135 64-87 50x 12 24
1965
ministrongylus strongyloxeas orthotriaenes x x rayed
Hechtel, 370-551 187-311 119-319 9-33/ray oxyaster
87-106 43-181 37-80 10-25
1-5 few
1-4
x orthotriaenes x x x
& strongyles x
gofrilleri Wieden- mayer, 1977 610-690 8-18 500-580 12-16 180-240 9-12 100-15065-95 oxeas 35-70 tylaster 20-61
x orthotriaenes x x x x2-3
Erylus. 600-1000 300-480 170-265 160-250
formosus Solías, 1888 10-20 12-19 7-12 20-55 38-55 tylaster 14-28 present
of
species
1986
x orthotriaenes x
31-50x2.5
bahamensis
West-Indian Pulitzer- Finali, 530-850 370-590 120-340 125-190 19-40 "thin" tylaster 15-28 10-12
6-15
of
Kilian,
characters
Wintermann- x plagiotriaenes x
amphiastera & amphioxeas x amphiaster
Kilian 1984 450-900 20-38 280-470 120-190 78-128 124-225 52-56 50-70 69-300
Spicule
centrotylote
1: species triaenes aspidaster microxeas I II
Table oxeas rhabd clad aster aster
144
Euryspongia). Family Polymastiidae Gray, 1868
Skeleton:Ectosome: discorhabdswithpoints facing GenusPolymastia Bowerbank, 1864
in are scattered over the surface, most of the
space in between is covered with microscleres. Polymastia fordeisp. n.
Choanosome: there is a rigid skeleton of Figs. 9-18
tetracrepid desmataand numerous oxeas strewn
inbetween. Material: Holotype: ZMA POR. 13456,
Spicules: Tetracrepid desmata, difficult to mea- Discovery Bay, LTS, 82 m, 21. 6. 96, #J96/30.
sure; long oxeas: 200-920 x 4-10 pm; discotri-
aenes, with disc 120-240 pm in diameter. Description: Dirty grey-brown, thickly encrusting
Microscleres in two size categories: small acan- sponge(Fig. 9) withafewwhitish conical papillae,
tilóse microxeas/microstrongyles: 12-16 x 3-4 1-2 cm long, diameter2 mmat the top, 6 mmat
pm, andlarge microxeas: 32-50 x 3-4 pm. base, with an apical oscule, 1 mm in diameter.
Remarks: According to M. Kelly (pers. comm.) this Cortex ca. 4 mm inthickness, standing out white
is a new species, which will be described in a against the yellowish interior. Surface hispid.
forthcoming publication. Thisis thesamespecies Very hard, incompressible.
whichwas described as D. dissoluta by Lehnert& Skeleton: Very dense arrangement of spicules in
Van Soest, 1996. Some specimens (#[96/47-1 & the three layers usual for the genus. In the ecto-
47-2, #J96/56-2) differ in size of the largcr some of the mainbody of the sponge the small
microsclere category which is here 64-96 x 3-4 tylostyles are present in dense masses, but not
|am. Thesecharacters were already mentionedin arranged in a proper palisade, as is usual in
the description of deep-water specimens from Polymastia, but in considerable confusion. This
Jamaica by Lehnert& Van Soest, 1996.All spec- layer hasa thickness of 400-500 ¡am. Incontrast,
imens differfrom the description of Discodermia the ectosomal tylostyles in the papillae are more
dissoluta given by Zea (1986) in having generally or less arranged in a palisade (Fig. 13). Below
larger oxeas. these, there is an area with a thickness of about
400 [im devoidof smaller megascleres, followed
Order Hadromerida by a layer of subectosomal intermediatespicules
Family Spirastrellidae Ridley & Dendy, 1886 arranged loosely but mostly parallel to the sur-
Genus Spirastrella Schmidt, 1868 face. This layer measures approximately 1200
jam. Thickspicule tractsstartfromfocal points in
Spirastrella coccinea (Duchassaing & the choanosome(Fig. 11), broaden outand over-
Michelotti, 1864) lap towards the surface (Fig. 10). These tracts
consist of strongyloxeas and they protrude con-
Material: ZMA POR. 13512, Discovery Bay, siderably beyond the confused layer of small
LTS, 91 m, 21. 6. 1996, #J96/22; ZMA POR. tylostyles. In the interior thick spicule tracts of
13515, Discovery Bay, Pinnacle II, 91 m, 5. 7. strongyloxeas make up the skeleton, arranged
1996, #J96/60-2; ZMAPOR. 13514, Discovery mainly parallel to the surface with numerous
Bay, Dairy Bull, 70 m, 27. 6. 1996, #J96/39-l; smaller tylostyles scattered in all directions.
ZMA POR. 13513, Discovery Bay, LTS, 88 m, Longitudinal sections through the papillae (Fig.
25. 6. 1996, #J96/32-7. 12) show a central canal, longitudinal arrange-
mentof tracts of strongyloxeas and anectosomal
Description: Bright orange or red encusting perpendicular palisade of (sub-) tylostyles (Fig.
sponges. Surface with skinny canals leading to 13).
oscules. Spicules: Main spicules are strongyloxeas to
Spicules: Tylostyles: 280-680 x 7-16|im; spirasters fusiform tylostyles, occasionally styles, sometimes
of widesize range: 16-42 ftm with a simple telescoped end (Figs. 14-15, 17):
Remarks: All specimens were growing over the 400-1914 x 10-52 (am; cortical (sub-)tylostyles
basal skeleton of Ceratoporella nicholsoni. (Figs. 16,18)in two size categories: large category,
225-355 x 7 -11 (am, small category, often with
145
Figs. 9-16:Polymastiafordeisp.n.,9. holotype ZMAPOR. 13456, 10,crosssection ofperipheral skeleton showing outercon-
fusedlayer of small tylostyles, subdermal corticallayer oflarge strongyloxeas, and lacunar layerof intermediatetylostyles
arrangedparallel tothe surface(scale = 500 µm), 11. subcortical section showingfocal points of tylostyle bundles (scale=
250 µm), 12. sectionofpapillarsurface with palisade of small tylostyles (scale= 100µm), 13. crosssection ofpapillashow-
ing longitudinalskeleton(scale = 250µm), 14. largestrongyloxeas, 15.detail ofstrongyloxea, 16. intermediate tylostyle.
146
Table 2.Atlantic species ofPolymastiawith strongyloxeas,and central WestAtlanticPolymastia.
principal intermediary ectosomal
strongyloxeas tylostyles tylostyles
P.inflata 620-1250x 250-660x 90-290x
11-18 11-26 3-5
P.infrapilosa 1700-1900 x 300-700 x ? 150-240x
23 7-8
P.grimaldi 1450-2275x 210-676 x 172-286 x
21-26 10.4-21 5.2-7.8
P.spinula 724.5-926.8 x 332.8-478.4x 124.8-156x
10.4-15.6 5.2-10.4 5.2
P.uberrima 1315-1770 x 556-754 x 307-350 x
17-25 8-10 5
P.corticata 1634-2106 x 674-893 x 166-255 x
17-34 10.4-15.6 5.2-10.4
P.littoralis 1000-1500 x 450-600 x 140-240x
27-30 upto 27 5
P.tenax 806-1100 (tylost.) x 320-420 x 130-330 x
13-26 18-30 2.5-9
P.janeirensis 838-1231 x 229-828 x 75-175 x
upto21 3-? 1.5-4.3
P.fordein.sp. 400-1914 x 225-355x 145-235 x
10-52 7-11 1-5
subterminal head (Fig. 18), occasionally polyty- those our species more subtylostylote) andinhav-
lotemalformations occur: 145-235x 1-5 |im. ing larger small tylostyles. Furthermore, P. inflata
Etymology: Namedafter PeterForde, who accom- is knownfrom the Eastern Atlantic only. It differs
panied HLonseveral trimix-dives. from P. infrapilosa in having thicker strongyloxeas
Remarks: According to Boury-Esnault (1987) and of a muchwider size-range and in having small-
Boury-Esnault et. al. (1994) there are 18 valid er intermediary tylostyles. P. infrapilosa has been
species of Polymastia in the Atlantic. Ten do not foundonly once NE of Halifax. It differs from P.
have strongyloxeas or fusiform tylostyles and are grimaldi in having fewer papillae, the principal
therefore different in spiculation. Eight of them strongyloxeas are smaller but thicker, intermedi-
(P. inflata Cabioch, 1968; P. infrapilosa Topsent, ary spicules are smaller of narrower size-range
1927; P. grimaldi (Topsent, 1913); P. spinula and thinner. It differs from P spinula in having
Bowerbank, 1866, P. uberrima (Schmidt, 1870), P. shorter papillae, longer and thicker principal
corticata Ridley & Dendy, 1886, P. littoralis strongyloxeas, and smaller, thinner intermediary
Stephens, 1915 and P.janeirensis (Boury-Esnault, tylostyles. It differs from P. uberrima in having
1971)) have strongyloxeas or fusiform tylostyles much thicker principal strongyloxeas of amuch
with additional tylostyles. Their spicule charac- wider size-range, in having smaller intermediary
tersare listed alongwiththose of our newspecies tylostyles and smaller small tylostyles. NE
inTable2. Adantic P. corticata has more than 100 papillae
P.fordei n.sp.differs fromall theseinhaving the and is not optically hispid, whereas P.fordei has
ectosomal tylostyles of the main body arranged only afewand is hispid. South African P.littoralis
in densely confused masses. Itdiffers from P.infla- likewise has numerous papillae andasmooth sur-
tain having longer and much thicker strongylox- face. Both P. corticata and P. littoralis have longer
eas, in having smaller and thinner intermediary intermediary tylostyles.
tylostyles (P. inflata with a well rounded head, P. janeirensisfrom Brazilis adarkpurple sponge
147
Figs. 17-18. Polymastiafordeisp.n., 17.small tylostyle, 18. detailofsmalltylostyle. Fig. 19.Pseudotrachyaamaza(DeLaubenfels,
1934), habit ofZMAPOR. 13547 (scale = 1 cm), Figs. 20-23.Dictyonellafoliaformis Lehnert &Van Soest, 1996, 20.pho-
tographed insitu before collection (scale = 1 cm), 21-22,differentparts ofthe choanosomal skeleton (scale = 250 µm), 23.
habitofflabellate specimenZMAPOR. 13535 (scale = 1 cm),Fig. 24.Axinella digitiformisLehnert & Van Soest, 1996,and
Phakelliabettinaen.sp. photographed insitu beforecollection (scale = 5cm).
148
with 30-60 papillae; its skeleton shows no gap apparently consistent difference, suggests distinct-
betweenthe ectosomal palisade and the parallel ness at the specific level, andaccordingly we pro-
layer of intermediary megascleres; spicule sizes pose here to assign Caribbean specimens to P.
differconsiderably withP. fordein.sp.(see Table2). amaza (De Laubenfels, 1934 as Anomolissa). The
The only sympatric Central West Atlantic hoiotypeof this species, USNM 22348, was mis-
Polymastia is P. tenax. This differs from our new interpreted by De Laubenfels, as he judged rare
species in having mammiformpapillae, and true and obviously foreign arcuate chelae to be evi-
tylostyles as themainmegascleres; theorientation dence forPoecilosclerid affinity of it.
of the intermediate spicules is perpendicular
ratherthan parallel with thesurface. OrderChondrosida
Family ChondrillidaeGray, 1872
Family Suberitidae Schmidt, 1870 Genus Chondrilla Schmidt, 1862
GenusPseudotrachya Hallmann, 1914
Chondrilla nucula Schmidt, 1862
Pseudotrachya amaza (De Laubenfels, 1934)
Fig. 19 Material: ZMA POR. 13516, Discovery Bay,
LTS, 4.7.1996, 107 m, #J96/51; ZMA POR.
Anomolissaamaza De Laubenfels, 1934: 17 13517, Discovery Bay, Pinnacle II, 5.7.1996, 85
Pseudotrachya hystrix; Van Soest & Stentoft, 1988: m J96/57-3. Lehnert collection: Discovery Bay,
79, pl. X fig. 1, text-fig. 39(not: Topsent, 1892) LTS, 4.7.1996, 107 m, #J96/32-4.
Material: ZMA POR. 13547, Discovery Bay, Description: Dark greyish blue, massively incrusting
Dairy Bull, 28. 6. 1996, 81 m,#J96/42. sponge. Surface smooth, no oscules visible.
Consistency like rubber.
Description: Thickly encrusting, orange-yellow Skeleton: Asters are densely packed in the ecto-
(alive) or pale brown (dry) coloured, very hard some to a thickness of about 400 |im. In the
sponge (Fig. 19). Size upto 4.5x4x1 cm. Surface choanosometheastersare irregularly distributed,
hispid, looking velvet-like dueto long projecting sometimes along canals, other areas may be
spicules. Round tooval oscules, 3-5 mmin diam- devoidofthem. Spherasters: 16-35 |_unindiame-
eter scatteredover the surface. ter.
Skeleton: Short but thick bundles of oxeas form Remarks: This seems tobe a very variablespecies.
spicule brushes at the surface and protrude Three growth forms occur in Jamaica: a dark
approx. 900|_im over thesurface. A denselayer of brownlumpy growth form which is restricted to
short oxeas, oriented perpendicular to the sur- lagoonal habitats, a light brown encrusting
face, 200-250 pm thick forms the ectosome. In growth form occurs on the shallow fore-reef and
the choanosome short and thick bundles of covers larger areas, and the third growth form is
spicules are facing inall directions. represented by this deep fore-reefspecimen.
Spicules: Oxeas of two size categories, large oxeas,
occasionally with one of the ends bluntly round- Order Halichondrida
ed: 480-1700x 15-40pm, small oxeas: 125-200x Family Halichondriidae
3-6 pm. GenusAxinyssa von Lendenfeld, 1897
Remarks: With the discovery of yet another
Caribbeanspecimen conforming to Pseudotrachya, Axinyssa ambrosia (De Laubenfels, 1934)
it has become increasingly clear that in the
Caribbeanthe sizes of the largest oxeas are con- Material: ZMA POR. 13545, Discovery Bay,
siderably smaller than those Pseudotrachya speci- LTS, 20.6.96, 85 m, #J96/14.
mens from the Mediterranean area. These are
only 500-1700 (amin theCaribbean, while 2000- Description: Orange coloured, relatively soft, mas-
7000 in the Mediterranean (Topsent, 1892; sive sponge.Easy to tear,surface lamellate. Many
Vacelet, 1969; Boury-Esnault et al., 1994). This long canals, about 1 cmin diameterreaching the
149
surface. Abundantsedimentparticles in the inte- rence of this species testified by the origin of the
rior. type specimen from a depth downto the 72 m.
Skeleton: Organic ectosome with only a few The species is also recorded from very shallow
spicules, someof whichare tangentially arranged reef andmangrovelocations.
but together do not form aspecialized ectosomal
skeleton. Surface with short conules, supported Topsentia bahamensis Diaz, Van Soest &
by spicule tracts, spicules protruding at thetop of Pomponi, 1993
conules. Choanosome with short, sometimes
branched, spicule tracts or spicules in confusion. Material: ZMA POR. 13543, Discovery Bay,
Single spicules and spicule tracts with consider- LTS, 20.6.1996, 79 m, #J96/18; ZMA POR.
able amounts of spongin. 13544, Discovery Bay, LTS, 25.6.96, 90 m,
Spicules: Oxeas with single or multiple telescoped #J96/32.
ends of irregular outline: 720-1160x 6-16 fini.
Remarks: Van Soest et al.'s (1990) assignment of Description: These are long thick chimneys, with
Axinyssa to the family Halichondriidae is here several long canals leading through the entire
maintained, despite thefactthatAxinyssa lacks the specimen. They conform to material described
ectosomal skeleton characteristic for Halichon- previously from the LTS location by Lehnert &
driidae. Hooper & Bergquist (1993) assigned the Van Soest, 1996. Spicules are in two size cate-
genus to Axinellidae, but that family has the gories (200-400 and 600-900 fim) rather than
spicules organized in a reticulation, which is three, and the larger sizes are somewhat smaller
entirely absent inAxinyssa. Thevague tracts and than those of T. ophirhaphidites.
fibrous choanosome fit more easily in the family
Halichondriidae. Family Desmoxyidae Hallmann, 1917
GenusJulavis de Laubenfels, 1936
Genus Topsentia Berg, 1899
Julavis jamaicensis Van Soest & Lehnert,
Topsentia ophiraphidites (De Laubenfels, 1997
1934)
Material: ZMA POR. 13516, Discovery Bay,
Material: ZMA POR. 13540, Discovery Bay, LTS, 4.7.1996, 106 m, #J96/51.
LTS, 19.6.1996, 76 m, #J96/7; ZMA POR.
13542, Discovery Bay, Pinnacle II, 5.7.1996, 85 Description: Very thinly (200-400 |xm) encrusting
m, #J96/57; ZMA POR 13541, Discovery Bay, on Chondrilla nucula, present in several thin sec-
Dairy Bull, 27.6.96, 76 m,#J96/38. tions.
Skœleton: Densely packed acanthostrongyles in
Description: Hard, cake-shaped to massive sponges, confusionwithsingle smooth long strongylostyles
grey or brownish-green in live, light brown to perpendicular to the surface. Scattered tri-
ochre-coloured in the dry state. The surface is chodragmas. Spicule dimensions as reported by
somewhat uneven and partially overgrown by Van Soest & Lehnert, 1997.
Halimedaand calcareous algae. Remarks: This is the second recordof the species
Skeleton:There is aconcentrationof smaller oxeas and the thirdfor this very rare genus.
near the surface and a confused arrangement of
spicules inthe interior. Genus Didiscus Dendy, 1922
Spicules: Three partially overlapping size cate-
gories ofoxeas, large ones:820-1280x22-35 |am, Didiscus oxeata Hechtel, 1983
intermediates: 320-690 x 6-11 (am, and small
ones: 128-330x 4-6 fim. Material: ZMAPOR. 13532, 13539, Discovery
Remarks: The spicule measurements conform to Bay, Dairy Bull,28.6.1996, 79m, #J96/47-3.
measurements given by Diaz etal., 1993.
The present record confirms the deep occur- Description: Yelloworange coloured, tough, fibrous
150