The genus Julavis de Laubenfels (Porifera: Halichondrida)

9 Pages·1997·3.9 MB·

PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON
110(4):502-510. 1997.
The genus Julavis de Laubenfels (Porifera: Halichondrida)
Rob W. M. van Soest and Helmut Lehnert
(RVS) Institute for Systematics and Population Biology (Zoological Museum),
University of Amsterdam, P.O. Box 94766, 1090 GT Amsterdam, Netherlands
(HL) Institut & Museum fur Geologie und Palaontologie, Goldschmidtstr. 3,
37077 Gottingen, Germany
—
Abstract. Julavis jamaicensis new species is reported from Northern Ja-
maica. This represents the second record of the genus and the first from the
Atlantic basin. Julavis de Laubenfels 1936 was erected to accomodate Tedania
levis Kirkpatrick 1900 from the Funafuti Atoll, Central Pacific. Its status was
never discussed prior to the present paper and order and family allocation
(Poecilosclerida: Acarniidae) have remained tentative. It is proposed to allocate
it to the order Halichondrida, family Desmoxyidae, on the basis of confused
skeletal architecture, possession of acanthose diactines and wispy trichodrag-
mas. The genus is distinguished from other genera of Desmoxyidae by its
smooth strongylostyles and by the strongylote nature ofthe acanthose diactines.
The contents of the family Desmoxyidae is discussed and compared with re-
lated families.
Kirkpatrick (1900) described from deep Recently, one of us (HL) collected an or-
waters (90-125 m) off the atoll ofFunafuti, ange encrusting sponge off the north coast
Central Pacific, a thinly encrusting sponge of Jamaica, with characters closely similar
with the unusual skeletal structure of a felt- to those of Tedania levis. This material is
work of spined strongyles with scattered described below as a species new to science
smooth strongyles, combined with frayed and compared to the type specimen of T.
trichodragmas. He named the species Te- levis borrowed from the collections of the
dania levis but admitted that it was "... Natural History Museum, London (BMNH).
only placed in Tedania provisionally, . . . In view of the fact that there are now two
should probably come under a new genus species answering to the definition of Ju-
near Tedania ... ". De Laubenfels (1936) lavis, it is proposed to consider the genus
in his monograph of the orders, families as valid. Its family and order allocation has
and genera of the Porifera erected a new to be changed from Poecilosclerida: Acar-
genus Julavis (origin of the name not ex- niidae, as proposed by de Laubenfels, to
plained) without having seen the original
Halichondrida: Desmoxyidae; this will be
material. His definition for the new genus
discussed below.
was: " two distinct categories of spiny
. . .
strongyles (sic) for megascleres and raphi- Julavis jamaicensis, new species
des for microscleres." This is a misrepre- Figs. 1-3
sentation of Kirkpatrick's description, as —
there are smooth and spiny megascleres Material examined. Holotype: Zoolog-
rather than two spiny types. Since then, as ical Museum Amsterdam, Porifera collec-
ZMA
with so many other "paper" genera of de tion, reg.no. POR.l 1520. Jamaica, off
m
Laubenfels, no further reference was made Chalet Caribe, Montego Bay in 20 depth,
in the literature on either Tedania levis or dried specimen.—
the genus Julavis. Description. Thinly encrusting on the
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surface of a large dead sclerosponge, Cer- oxea-like spicules (Fig. 3.5). Size 52-152
atoporella nicholsoni (Porifera: Ceratopo- X 2-8 fxm.
rellidae). The type specimen was sawed out Ecology: the sclerosponge encrusted by
of the basal skeleton of a large (25 cm di- the new species was collected in a c—ave.
ameter) specimen of the sclerosponge (Fig. Comparison with Tedania levis. The
mm BMNH
1). It is about 1 thick, lateral expansion type specimen of T. levis,
mm
at least 10 X 15 cm. Surface in dry con- 1900.10.19.16, is a thin crust of 1.5 on
dition smooth, hard, crumbly, difficult to a small piece of coralline alga. It has the
section tangentially. No visible oscules or same appearance and consistency as Julavis
openings. Colour light orange to beige. jamaicensis. Differences between the two
Skeleton (Figs. 2A-B) in dry condition a species are mostly confined to details of the
packed feltwork of confusedly arranged spicules (Table 1). The acanthostrongyles
acanthostrongyles with occasional single form the same felted mass as in J. jamai-
smooth long spicules in a position perpen- censis, but the uppermost are tangentially
dicular to the surface. The outermost acan- arranged (Fig. 4A-B), rather than in a pal-
thostrongyles tend to form an irregular pal- isade. The acanthostrongyles (Figs. 4C,
isade with apices pointing outward at dif- 5.1-2) are much more strongly curved and
ferent angles. Rarely, the smooth long spic- distinctly longer and thinner than those of
ules form bundles. Trichodragmas are J. jamaicensis: 211-340 X 7-14. The long
scattered throughout the spicule mass. The smooth spicules (Figs. 4E, 5.3) closer to
typical strongyles, although they also show
organic parts are greatly reduced (no doubt
somewhat unequal ends. Their sizes appear
due to shrinking). There is no recognizable
to be somewhat longer: up to 1385 X 4-12
spongin, but the narrow space between the
A
|xm. shorter category of styles reported
spicules is definitely fibrous.
by Kirkpatrick (245 urn) appears to be for-
Spicules (Figs. 2C-E, 3, Table 1) include
eign. The trichodragmas (Figs. 4D, 5.4-6)
acanthostrongyles, strongylostyles and tri-
are similar but longer than those of /. ja-
chodragmas. Acanthostrongyles (Figs. 2C,
maicensis: 144—203 X 3-12 urn.
3.1-3) are in majority entirely covered by
These skeletal differences in themselves
coarse blunt spines; they are somewhat ir-
do not form an impressive load of evidence
regularly shaped, often curved, with apices
for specific distinctness between the two
slightly narrower than the shaft. Occasion-
specimens because specific variation is un-
ally they are almost entirely smooth (Fig.
known. However, the wide geographic sep-
3.2) or smooth asymmetrically at one of the
aration of the recorded specimens supports
ends (Fig. 3.3); juvenile spicules are finely these small morphological differences and
acanthose, almost smooth, oxea-like (Fig. we erect the new species with confidence.
—
2C, middle spicule). Size 127-258 X 8-20 Generic allocation. De Laubenfels
|xm. Strongylostyles (Figs. 2D, 3.4) are (1936) erected Julavis on the basis of the
smooth, style-like but conically rounded at incompatibility of the described characters
one end and often rather bluntly pointed or of Tedania levis with those of the genus
stair-stepped at the other. Occasionally the Tedania. It is clear from recent discussions
conical end is rhabdose, i.e. abruptly on the contents of Tedania and the family
curved. They are rare both in sections and Tedaniidae (e.g., in Desqueyoux-Faundez &
in dissociated spicule mounts and invari- van Soest 1996) that de Laubenfels was
ably broken. Size up to at least 850 X 4-8 correct in removing T. levis from Tedania.
urn. Trichodragmas (Figs. 2E, 3.5-6) form The synapomorphy for Tedaniidae, i.e., on-
wispy, straight or S-curved bundles of 12- ychaetes, is lacking in T. levis. With two
20 raphides. Bundles may be entirely related species known, use of the genus Ju-
sheathed and then superficially resemble lavis is certainly justified. It remains a rare
504 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON
Fig. 1. Julavisjamaicensis new species, photo of holotype encrusting Ceratoporella nicholsoni.
genus with only two records at opposite niidae de Laubenfels, 1936 is a junior syn-
sides of the world, perhaps indicating a onym ofMicrocionidae Carter, 1875. Julav-
wider Tethyan distribution. — is needs to be removed from Acarniidae/
Family and order allocation. The ma- Microcionidae because it lacks the ectoso-
jor problem with Julavis is the family and mal subtylostyles, toxas and palmate iso-
order allocation. De Laubenfels (1936) as- chelae characteristic for this family.
signed Julavis to the family Acarniidae, The skeletal architecture and spicule
erected for an odd assortment of genera, in- complement would allow allocation to both
cluding among others Sceptrintus (now Poecilosclerida (e.g., family Crellidae) and
Hadromerida: Latrunculiidae), Janulum Halichondrida (e.g., families Desmoxyidae
(Poecilosclerida: Raspailiidae), Jelissima and Halichondriidae).
(Poecilosclerida: Myxillidae) and Jones Crellidae have a surface crust of acan-
(Poecilosclerida: Coelosphaeridae). The thoxeas or acanthostyles and a choanosomal
type genus of the family Acarniidae is skeleton consisting of bundles of smooth
Acarnia Gray, 1867, erected for type spe- tornotes, which may be oxea-like, strongly-
cies Hymeniacidon cliftoni Bowerbank, like or style-like. Normally there are chelate
1864, which is a junior synonym of Clath- microscleres and short echinating acantho-
riafrondifera (Lamarck 1814) (see Hooper styles, but these may be absent. Allocation
&
Wiedenmayer 1994: 256). Thus, Acar- of Julavis to Crellidae is not warranted for
.
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110, 4 505
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Fig. 2. Julavisjamaicensis n. sp., drawings of skeleton and spicules. A, surface view ofectosomal skeleton;
B, cross section; C, various growth stages of acanthostrongyles; D, trichodragmas; E, smooth style and stron-
gylote modification.
506 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON
Fig. 3. Julavisjamaicensis n. sp., Scanning electronic microscope (SEM) photos ofthe spicules. 3.1, a fully
spined acanthostrongyle (X650); 3.2, virtually smooth "acanthostrongyle" (X650); 3.3, partly smooth, partly
spined acanthostrongyle (X650), 3.4, style (X650); 3.5, sheathed trichodragma X2200); 3.6, irregularly fanned-
out trichodragma (X2200).
the following reasons: Crellidae tend to be two families is still in debate: for example,
soft sponges with surface areolae or veinal Ptilocaulis, assigned to Desmoxyidae by
canals visible; the tangential surface crust van Soest et al. (1990) on account of its
is generally thin (single spicule layer) and gross morphological similarity to certain
strictly tangential; the acanthose spicules Higginsia species, was shown to be very
are never strongyles; the tornotes are sel- close to Axinella of the family Axinellidae
dom longer than 300 fxm and never over by Alvarez et al. (1997); the allocation of
600 u-m; and, no trichodragmas have been Axinyssa and Myrmekioderma to Halichon-
&
recorded from Crellidae. driidae is disputed by Hooper Bergquist
&
Halichondriidae and Desmoxyidae are (1992) and Hooper Levi (1993).
considered closely related families in a re- Myrmekioderma shares several features
defined order Halichondrida by van Soest with Julavis: spined diactinal surface spic-
et al. (1990). The generic content of these ules (oxeas in Myrmekioderma), smooth
VOLUME NUMBER
110, 4 507
—
Table 1. Comparison of spicule types and sizes (|xm) of Julavis levis (Kirkpatrick 1900) and J. jamaicensis
n.sp. (ranges, means in italics).
Spicule type Julavis levis Julavisjamaicensis
Acanthostrongyles 211-280.5-340 X 7-77.7-14 127-785.2-258 X 8-74.7-20
Strongylostyles* <1385 X 4-12 <850 X 4-8
Trichodragmas 144-775.5-200 X 3-3.8-12 52-108.3-152 X 2-J.7-8
* Most often broken in the spicule slides.
diactinal choanosomal spicules (oxeas in diactinal surface spicules (shared with Hig-
Myrmekioderma), and wispy trichodrag- ginsia) and wispy trichodragmas (shared
mas. The two genera are nevertheless con- with Myrmekioderma). It is sufficiently dis-
sidered to be distinct because spination of tinct from both in possessing acanthostron-
the surface spicules in Myrmekioderma is gyles in a thick surface feltwork. Accord-
very fine (and may be occasionally absent) ingly we propose to include Julavis in a re-
and the choanosomal spicules are arranged arranged and redefined family Desmoxyi-
in definite tracts. The surface of the known dae, which in disagreement with van Soest
species of Myrmekioderma shows a char- et al. (1990) receives Myrmekioderma and
acteristic groove pattern (see van Soest et the closely similar Didiscus from the family
al. 1990). Halichondriidae, and loses Ptilocaulis to
A
further genus sharing features with Ju- the family Axinellidae.
—
lavis is Heteroxya Topsent, 1904. Van Soest Family Desmoxyidae. Halichondrida
et al. (1990) tentatively considered it a ju- with a surface skeleton consisting of spined
nior synonym of Myrmekioderma, but the diactinal spicules (oxeas or strongyles); the
evidence for that assumption is weak. The choanosomal skeleton is formed either by a
genus is defined as having spined and confused or perpendicular arrangement of
smooth oxeas in a confused mass, with single spicules or interconnected bundles
smaller spined oxeas forming a dense pal- perpendicular to the surface.
isade at the surface. No trichodragmas have Higginsia Higgin, 1877 (jun. syn. Des-
been reported from the type and only as- moxya Hallmann 1917): spined oxeas with
signed species, H. corticata Topsent, 1904. abrupt angular curve in the middle; choan-
The strongylote and stylote spicules as well osomal skeleton an elaborate system of
as the possession of trichodragmas easily bundles of megascleres.
differentiate Julavis from Heteroxya. Halicnemia Bowerbank, 1866: spined
Another genus that needs to be consid- oxeas with abrupt angular curve in the mid-
ered is Higginsia (Desmoxyidae), which dle; two categories of choanosomal mega-
likewise shares with Julavis diactinal scleres one of which is erect on the sub-
spined surface spicules (oxeas) over much strate while the other surrounds the first.
longer smooth choanosomal spicules. The Heteroxya Topsent, 1904: Surface skele-
two genera are considered distinct because ton a palisade of smaller spined oxeas,
the spined oxeas of Higginsia have a dis- though which perpendicular subectosomal
tinct angular curve in the middle. These longspined oxeas protrude; choanosomal
spicules often do not form a surface crust skeleton a confused mass of smooth and
but are scattered among the choanosomal spined oxeas.
megascleres. The choanosomal skeleton Myrmekioderma Ehlers, 1870: surface
consists of well-defined tracts of smooth oxeas rugose or finely spined; choanosomal
megascleres. megascleres in several length categories ar-
Julavis links Higginsia and Myrmekio- ranged in a system of interconnected tracts;
derma by its possession of coarsely spined microscleres wispy or straight trichodrag-
508 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON
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'////////s/////////////
BMNH
Fig. 4. Julavis levis (Kirkpatrick), holotype 1900.10.19.16, drawing of skeleton and spicules. A,
surface view of ectosomal skeleton; B, cross section; C, various growth stages of acanthostrongyles; D, tri-
chodragmas; E, smooth strongyle.
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110, 4 509
BMNH SEM
Fig. 5. Julavis levis (Kirkpatrick), holotype 1900.10.19.16, photos of the spicules. 5.1, acan-
thostrongyle (X300); 5.2, detail of part of acanthostrongyle (X800); 5.3, terminal part of smooth strongyle
(X800); 5.4, sheathed trichodragma (X300); 5.5, partly split-open trichodragma (X300); 5.6, detail of trichod-
ragma (X2200).
mas; surface has characteristic sinuous of long strongylostyles arranged singly per-
grooves. pendicular to the surface; wispy trichodrag-
Didiscus Dendy, 1922: surface oxeas ru- mas.
gose or finely spined, possessing two un-
equally sized discs assymmetrically along
Acknowledgments
the shaft; choanosomal megascleres in sev-
eral length categories arranged in a system HL was funded by the Deutsche For-
of interconnected tracts; surface has char- schungsgemeinschaft (Re 665/10-1) and
acteristic sinuous grooves. thanks Prof. Dr. Joachim Reitner, the pro-
Julavis de Laubenfels, 1936: surface ject leader. Thanks also to the dive-buddies
spicules are coarsely spined strongyles Greg Lee and Jean Luc Solandt and to the
forming a thick felted mass at the surface; "Reefkeepers", Montego Bay who sup-
choanosomal skeleton reduced, consisting plied boat and tanks. This is contribution
510 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON
—
Nr. 591 of the Discovery Bay Marine Lab- es. Memoirs of the Queensland Museum
32(1):99-137.
oratory, Jamaica. -, & C. Levi. 1993. Axinellidae from the New
Ms
Clare Valentine graciously sent us the Caled—onian lagoon (Porifera: Demospon-
specimen of Tedania levis on loan. Louis giae). Invertebrate Zoology 7(6):1395-1472.
&
Van der Laan (ZMA) made the habit pho- -, F. Wiedenmayer. 1994. Porifera. in: A.
tograph; Jan Vermeulen (ZMA) made the Wells, ed., Zoological Catalogue of Australia.
SEM photos. John Hooper (Brisbane) gave Volume 12. Melbourne, CSIRO, Australia, 612
pp.
valuable advice. Kirkpatrick, R. 1900. Descriptions of sponges from
—
Funafuti. Annals and Magazine of Natural
History (7)6:345-362.
W
Literature Cited Laubenfels, M. de. 1936. A discussion of the
sponge fauna of the Dry Tortugas in particular
Alvarez, B., R. W. M. van Soest, & K. Rutzler. 1997. and the West Indies in general, with material
for a revision of the families and orders of the
Revision of the Central West Atlantic Axinel- —
— Porifera. (Publications of the Carnegie Insti-
lidae. Smithsonian Contributions to Zoology tute Washington 467) Publications of the Dry
(in press). W Tortugas Laboratory 30:1-225.
Desqueyroux-Faundez, R., & R. M. van Soest. Soest, R. W M. van, M. C. Diaz, & S. A. Pomponi.
A
1996. review of Iophonidae, Myxillidae and 1990. Phylogenetic classification of—the Hali-
Tedaniidae occurring in the—South East Pacific chondrids (Porifera, Demospongiae). Beaufor-
(Porifera: Poecilosclerida). Revue Suisse de tia 40(2):15-62. —
Zoologie 103(l):3-79. Topsent, E. 1904. Spongiaires des Acores. Resultats
Hooper, J. N. A., & P. R. Bergquist. 1992. Cymbas- des Campagnes Scientifiques du Prince Albeit
tela, a new genus of lamellate coral reef spong- ler de Monaco 25:1-280.