Hydroids (Cnidaria: Hydrozoa) from southern Queensland

18 Pages·2002·9.4 MB·

by  J E Watson

Memoirs of the Museum of Victoria 59(2): 337-354 (2002)
HYDROIDS (CNIDARIA: HYDROZOA) FROM SOUTHERN QUEENSLAND
Jeanette E. Watson
Honorary Associate, Museum Victoria, P.O. Box 666E, Melbourne, Vic. 3001, Australia
e-mail: jewatson(aJbigpond.com
Abstract
Watson, J.E., 2002. Hydroids (Cnidaria: Hydrozoa) from southern Queensland. Memoirs of
Museum Victoria 59(2): 337-354.
Fifteen species of hydroids were collected from a reef off Palm Beach, southern Queensland.
Six records are new for Queensland; several species are circumtropical and two are
cosmopolitan. Symplectoscyphus sihogae is recorded for the first time outside the type
locality of Indonesia.
Introduction 15 species of hydroids. Six species, Eudendriitm
glomeratum, Hydrodendron daidalum. Salacia
A collection of hydroids was made on 9 May
desmoides, Symplectoscyphus sihogae. Agla-
2001 by the author using SCUBA from a reef
ophenia sinuosa and Ohelia angulo.sa and are
approximately I km offshore from Palm Beach,
new records for Queensland, having been previ¬
southern Queensland (28°5'52"S, I53°26'34"E).
ously recorded from temperate southern Australia
In this area, a reef system extends 1-2 km off¬
and tropical northern Australia. Pcnnycuik (1959)
shore along the coast at a depth of 5-15 m, sev¬
recorded 46 species from the Queensland coast
eral higher parts of the reef being emergent as
between the New South Wales border and
small islets. The water regime in the area is sub¬
north of Moreton Bay (latitudes 26-28°S). As
tropical, the temperature at the time of the survey
only four species in the present collection (Anten-
being 26°C. While not subject to .strong currents
nella secundaria, Synlhecium campyhearpum (=
the reefs arc exposed to swells of the South
S. patulum), Hincksella cylindrica, Macror¬
Pacific Ocean.
hynchia philippina) were recorded from this
The reef surrounding Cook Island off Burleigh
region by Pennycuik, the number of known
Heads was inspected but yielded no hydroids.
species from southern Queensland is thus
This island is a marine sanctuary, the surrounding
increased to 57.
waters being closed to recreational fishing; the
Several species in the present collection are cir-
invertebrate reef community is heavily grazed by
cumtropical in distribution, and two (Halecium
fishes. In contrast, the reef off Palm Beach, out¬
sessile and Antennella secundaria) arc cos¬
side the protected area and subject to consider¬
mopolitan. Symplectoscyphus sihogae is recorded
able recreational fishing pressure, has fewer fish
for the first time outside the type locality of
and the invertebrate community is much more
Indonesia. The collection also contains a small
diverse and abundant.
colony of a species of Halecium that could not be
With the exception of Macrorhynchia philip-
matched with any known species and may there¬
piiui and Aglaoplienia sinuosa which grow on
fore be new. In the following descriptions only
exposed reef surfaces all species w'ere small and
those synonymies relevant to Australia or the
cryptic, mostly occurring in sheltered crevices.
.southern hemisphere are given. Material is
Colonies of M. pliilippina, a tropical species,
deposited in Museum Victoria (NMV).
were quite small, indicating that it may be near
the southern end of its range. Colonies of List of Species.
A. sinuosa, the other visually dominant hydroid, Eudendrium 'Iglomeratum Picard, 1951
showed evidence of grazing by fish. Hehellopsis scandens (Bale, 1888)
The collection, made in one dive over an area Halecium sessile Norman, 1867
of several hundred square metres of reef, yielded Halecium sp.
337
338 J. E. WATSON
Hydrodendron daidalum (Watson, 1969). Leptothecatae
Salacia desmoides (Torrey, 1902)
Lafoeidae A. Agassiz, 1865
Dvnamena qiiadridentala (Ellis and Solander,
1786) Hehellopsis Hadzi, 1913
Dynamena qiiadridentala (Ellis and Solander,
Hehcllopsis scandens (Bale)
1786)
Symplectoscyphus sibogae (Billard, 1924) Figure lA
SytUhecitim campylocarpum Allman, 1888
Lafoea scandens Bale. 1888: 758.—Billard, 1904:
Hincksella cylindrica (Bale, 1888) 481.—Billard. 1906: 174.—Warren. 1908: 272, 341,
Antennella secundaria (Gmelin, 1791) 349.
Lyiocarpia brevirostris (Busk, 1852) Hchella scandens.—Marktanner-Tumeretscher, 1890:
Aglaophenia sinuosa Bale, 1888 214.—Millard. 1975: 182.—Migotto, 1996: 26.—
Macrorhvnchiaphilippina (Kirchenpauer, Watson, 1996: 78.— Boero et al., 1997: 8.
1872) Hehellopsis scandens.—Vannucci-Mendes 1949:
Obelia angulosa Bale 1888 237.—Vannucci-Mendes, 1950: 85.—Calder, 1991:43,
45. 95.
Anthoathccatae Material examined. Palm Beach, Queensland, 2 km
offshore, depth 5-15 m. NMV F91284, infertile
Eudendriidae L. Agassiz, 1862 colonies epizoic on Dynamena qiiadridentala, alcohol
preserved.
Eiidendriiiin Ehrenbcrg, 1834
Description. Stolons tubular, very thin, wrinkled,
Eudendrium Iglomeratum Picard
closely adpressed to the hydrorhiza of Dynamena
Eudendrium glomeratum Picard, 1951: 338.—Picard. quadridentata, then ninning up stem of host.
1955: 183.—Teissier, 1965: 14.—Watson, 1985: Hydrotheca tubular, issuing beside or between
213.—Boero and Cornelius. 1987: 244.—Watson, hydrothecae of host. Pedicel short, thin, tubular,
1996: 78.—Watson, 1999: 7. wall of hydrotheca obtusely flexed about halfway
Eudendrium genendis von Lcndenfeld, 1885: 351.—
along length, creased al bend; rim of hydrotheca
Thornely. 1904: 110.—Jaderholm, 1916:3.
circular, transverse to hydrothecal axis, slightly
Eudendrium indopacificum Stechow, 1924: 59.
thickened and very W'cakly outrolled. Perisarc
Material examined. Palm Beach, Queensland, 2 km off¬ rather thin, fragile at hydrothecal margin.
shore, depth 5-15 m, NMV F91283, several infertile
Hydranth with about 12 tentacles deeply with¬
stems to 4 mm high on barnacle, alcohol preserved.
drawn into hydrotheca (preserved material).
Description. Stolon tubular, entwining substrate. Colourless.
Stems unfascicled, unbranched or sparingly
Distribution. Cosmopolitan.
branched in one plane; hydranths terminal on
short pedicels or on single pedicels arising Remarks. The narrow stolon of //. scandens can
directly from stolon. Cnidome comprising small only be distinguished from that of D. quadriden¬
microbasic curyteles in tentacles and macrobasic tata as a thin, almost invisible tube lying closely
euryteles on hydranth body. Colour, stems brown, beside the broad hydrorhiza of the host. The
hydranths white. colonies of H. .scandens contain neither straight
nor slightly asymmetrical hydrolhecae conform¬
Distribution. Previously known in Australia from
ing to the accepted concept of H. scandens. Vari¬
the tropical north and north-western coasts
ous authors (Vervoort, 1968; VervooiT and
(Watson. 1999).
Vasseur, 1977; Boero et al.. 1997) have reported
Remarks. The material is doubtfully assigned straight and contorted hydrothcca in the same
to E. glomeratum based on the presence of colony of //. scandens W'hile hydrothecae of
macrobasic euryteles distributed over the H. scandens from norlhcni Australia were all con-
hydranth body. Although the nematocysts w'ere rorted (Watson, 2000). While it is possible that
not aggregated in pads on the hydranth as is //. .scandens may undergo torsion as a response to
normal in this species, reduction or loss of dis¬ ecological conditions it is nevertheless possible
crete pads and spreading of nematocysts over the that there may be two closely related species
entire hydranth body sometimes occurs (Watson, involved, one with almost symmetrical hydrothe¬
pers. obs.). If indeed E. glomeratum it is the most cae and one with contorted hydrothecae. This cati
southerly record of the species in Australian only be resolved with further collecting of an ade¬
waters. quate live material over a wide geographical
HYDROIDS FROM SOUTHERN QUEENSLAND 339
Figure 1. A, HebeUopsis scandens (Bale, 1888). Three hydrothecac on Dynamem qiiadridentala. B, C, Halecmm
sessile Norman, 1867. B, part of branch; C, stem inlernodes with hydrothecae. D, E. Halecmm sp. D, part of colony
with stolonal hydrothecae and erect stem; E, hydrophores and hydrothecae. F, Hydrodendnm daidaliim (Watson,
1969). Hydrorhiza, stem, hydrotheca and nematophore. Scale bar: A, D, C, 6.5 mm; B, 1 mm; E, 0.1 mm;
F, 0.2 mm.
340 J. E. WATSON
range and detailed investigation of reproductive Halediiiii sp.
strategies.
Figures 1D, E
Material examined. Palm Beach. Queensland, 2 km off¬
Haleciidae Hincks,1868
shore, depth 5-15 m, small infertile colonies on Ohelia
Haled lint Oken, 1815 angulosa (NMV F9I294) and Salacia desmoides
(NMV F91287), alcohol preserved.
Haleciiiiii sessile Norman
Description. Stolon straggling, tubular, faintly to
Figures 1B, C strongly rugose. Stems simple, very short, arising
Halecitim sessile Norman. 1867: 205.—Ritchie, at inter\als from hydrorhiza; basal stem intem¬
1911: 812.—Stechow, 1913: 9.—Billard. 1927: 329.— odes long, tubular, smooth, nodes deep, trans¬
Picard. 1958: 192.—Ralph, 1958: 331.—Pennycuik, verse. intemode tumescent above node. Primary
1959: 174.—Teissier, 1965: 21. -Vervoort. 1966: hydrophorcs given off singly from stolons and
100.—Redicr, 1967: 386.—Vervoort, 1968: 95.— di.stally on stem intemodes, outwardly bent, suc¬
Schmidt. 1972: 42.—Cornelius, 1975: 406.—Millard. ceeding intemode arising from a short apophysis
1975: 154.—Watson. 1979:234.—Ramil and Vervoort.
below hydrophore. Primary hydrophore fairly
1992: 85.—Watson, 1994: 66.—Cornelius. 1995:
short, cylindrical, surmounted by a deep, bowl¬
292.—Hirohito, 1995: 27.
shaped hydrotheca; rim of hydrotheca strongly
Material examined. Palm Beach. Queensland, 2 km off¬ outrolled; diaphragm distinct, a clearly visible
shore, depth 5-15 m, NMV F 91285, sparingly
ring of peg-shaped desmocytes above. Secondary
branched infertile colonies on various invertebrate sub¬
and tertiary hydrophorcs arising from diaphragm
strates in crevices, alcohol preserved.
of primary hydrotheca, usually several proximal
Description. Flydrorhiza reptant on substrate, constrictions in perisarc of hydrophore just above
stolons tubular. Stems monosiphonic, to 4 mm diaphragm. Perisarc of colony rather thin
high, straight to slightly zig-zag, simple or throughout. Hydranth too contracted for tentacle
sparsely branched near base. Stem intemodes count. Colour, white (preserved material).
widening distally to hydrophore, nodes trans¬
Remarks. The colony is so minute that it was
verse, deep. Hydrophore short, primary
noticed only during microscopical examination of
hydrotheca very shallow, sessile or very closely
Obelkt angulosa. The rather tangled stolon is eas¬
adpressed to intemode at level of node, shallow
ily detached from the substrate, the few stems
dish-shaped, sloping gently downwards away
being difficult to dilTerentiate from the stolons.
from internode, diaphragm distinct with a row of
The specimen bears no resemblance to any of the
desmocytes above. Margin circular, not everted.
smaller species of Halecitim known from Aus¬
Secondary hydrophorcs rare, on lower parts of
tralian waters, In size of colony and morphology
stems, issuing from diaphragm of preceding
of the hydrotheca it somewhat resembles H. pyg-
hydrotheca, adcauline wall deeply indented at
maetim Fraser, 1911; but dimensions are greater
level of diaphragm. Perisarc smooth throughout,
than those given by Hirohito (1995) for that
thick on proximal parts of stems, becoming very
species. Since many haleciids cannot be accu¬
thin on hydrotheca. I lydranths robust, very exten¬
rately identified in the absence of the gonosome,
sible with about 24 stubby tentacles. Colour yel¬
the material is not presently assigned to species.
lowish-brown.
Disiribiilion. Cosmopolitan. Recorded in Aus¬ Hydrodendron Hincks, 1874
tralia from southern Queensland to Bass Strait.
Hydrodeitdroii daidaliiiii (Watson)
Remarks. Secondary intemodes are sometimes
Figure IF
present between the main stem intemodes. The
material is assigned to Haleciitm sessile because Scoreshia daidaia Watson, 1969: 111.—Watson,
of the almost straight stems and rather shallow, 1979: 234.—Watson. 1982: 92. -Stranks, 1993: 6.
Hydrodendron daidalum.—Rees and Vervoort.
sessile primary hydrothccae. Although H. sessile
1987: 22.
was originally described from the cool temperate
northern Atlantic there are now many records Material e.xamined Palm Beach, Queensland, 2 km olT-
from other parts of the world, although some may shore. depth 5-15 m. NMV F91286. infertile colony on
be incorrect. Until a full world review of the the brown alga Zonaria crenata, alcohol preserved.
species is undertaken, it is best to refer the Description. Hydrorhiza a reticulating network
Queensland material to H. sessile. covering algal surface; stolons very wide, flat and
HYDROIDS FROM SOUTHERN QUEENSLAND 341
ribbon-like, outer flanges with dark excavations. transverse to intemode, straight or downwardly
Hydrotheca distal on a short, thick, deeply rugose convex. Hydrotheca narrowing somewhat to mar¬
pedicel, deep bowl-shaped, rim circular, slightly gin; margin oblique to both intemodal and
everted. Nematothecae small, elongate urn¬ hydrothecal axes, operculum of one valve
shaped, inserted on hydrorhiza beside hydrothecal attached inside abcauline margin. Perisarc
pedicel, margin circular with everted rim. smooth, rather thick in lower stem region, thinner
Hydranth with thick dome-shaped hypostome and but firm on hydrothecac. Hydranth with about 20
20-24 tentacles too large to retract into tentacles. Colour, deep yellow.
hydrotheca. Nematophore long, extensile, armed
Distribution. California, south-west Indian
with a distal cluster of nematocysts. Colour, pale
Ocean, Mediterranean Sea. Recorded previously
honey-yellow.
in Australia from Houtman Abrolhos Is, Western
Dislrihulion. This record extends the range of H. Australia. A new record for the Australian east
daiJalum from southern Australian coastline to coast.
warmer subtropical waters of the central east
Remarks. The intemodes of the present material
coast. Endemic to Australia.
are much shorter and the hydrothecae thus closer
Remarks. H. daidalum is an obligate epiphyte of together than in specimens described from the
the small brown alga Zonaria crenata, the Houtman Abrolhos Is by Watson (1997). The
hydrorhiza and widely spaced pedicels fomiing oblique margin with abcauline opercular valve is
an easily recognisable network on the algal thal- characteristic of the species.
lus (Watson, 1969). Although Rees and Vervoort
(1987) synonymised Scoreshia with Hydroden- Dynamena Lamouroux, 1812
dron there arc nevertheless several points of dif¬ Dynamena qiiadridentata (Ellis and Solander)
ference such as the simple, pedicellate stems and
stolonal nematothecae that set H. daidalum apart Figure 2C-F
from the typically branched colonies and cauline Seiiularia qiiadridentata Ellis and Solander, 1786:
nematothecae of the accepted concept of 57.—Lamarck. 1816:2, 121.
Uydrodendron. Dvnamena quadridentata.—Billard, 1925: 194,
222!—Trebilcock, 1928: 23.—Blackburn. 1938:320.—
Sertulariidae Lamouroux, 1812 Blackburn, 1942: 113.—Pcnnycuik, 1959: 193.—
Ralph, 1961:790.—Mammen,l965: 49.—Ralph, 1966:
Salacia Lamouroux, 1816 159.—Shepherd and Watson, 1970: 140.—Millard,
1975: 266.—Gibbons and Ryland, 1989: 411.—Calder,
Salacia desmoides (Torrey)
1993: 68.—Vervoort, 1993: 108.—Calder, 1995:
Figure 2A, B 543.—Hirohito. 1995: 176.—Watson. 1996: 78.—Wat¬
son, 1997: 520.—Watson. 2000: 15
Seiiularia desmoides Torrey, 1902: 65.—Billard, Pasya qiiadridentata.—Stechow, 1922: 148.—Ste¬
1924a: 66.—Fraser, 1938: 110.—Fraser, 1948: 247.— chow, 1923: 166.—Fraser, 1948: 239.
Stechow, 1923: 213.—Millard. 1975: 274.—Watson. Pasythea (Seiiularia) quadridentata.—Lamouroux,
1996: 78.—Watson, 1997: 518.—Medel and Vervoort, 1812: 183.—Lamouroux. 1816: 156.—Whitelegge,
1998: 30. 1889: 193.—Nutting, 1927: 226.—Yamada, 1959: 58.
Dynamena lhankasseriensis Mammen, 1965: 48.
Material examined. Palm Beach, Queensland, 2 km off¬
shore, depth 5-15 m, NMV F91287, infertile colony on Materiale.xamined. Palm Beach, Queensland, 2 km ofl-
bryozoan, alcohol presen ed. shore, depth 5-15 m. NMV F9I288. sparingly fertile
colony on the bryozoan Fhisira sp. and infertile colony
Description. Hydrorhiza loosely replant on sub¬
on red alga, alcohol preserved.
strate, stolon tubular. Stems short, unbranched,
proximal stem of same diameter as stolon, athe- Description. Hydrorhiza replant on substrate,
cate, ending in a strong V-shaped joint; stem stolon flat, wide and ribbon-like, edged by a
thereafter thecate. Internodes slender, conical, llange and canal with irregular, cusp-like indenta¬
nodes usually V-shaped, sometimes transverse. tions. Stems short, 2-4 mm long, widely spaced
Hydrothecae biscriate, paired, tubular, situated along hydrorhiza, proximal stem intemode athe-
about two-thirds distance up inlemode, adcauline cate with a strongly twisted V-shaped distal node,
walls conjoined, parallel to intcrnodal axis, internodes thereafter hydrothecate, vv'ith 1—4 pairs
straight to slightly convex, free adcauline wall of hydrothecae, nodes between sets of hydro¬
directed outwards in convex curve, abcauline wall thecae obscure, usually represented by constric¬
sinuous to flatly concave, floor of hydrotheca tion of perisarc. Hydrothecae biscriate, opposite.
342 J. E. WATSON
Figure 2. A, B, Salacia desmoides (Torrey, 1902). A, part of stem; B, intemodes with hydrothecae. 2C- F, Dyna~
menu quadridentata (Ellis and Solander, 1786). C, hydrorhiza and hydrothecate stem internode; D, anterior view of
hydrotheca; E, lateral view of hydrotheca with operculum; F, gonothecae. Scale bar; A, F, I mm; B, C, 0.5 mm;
D, E, 0.1 mm.
elongate saccate, adcauline walls in partial con¬ Floor of basal group transverse, thick, a basal
tact across intemode, conjoined walls straight to abcauline swelling forming a wide tunnel through
convex, remaining adnate and free adcauline wall perisarc; base of adcauline wall with large knob,
bent outwards to margin, floor of hydrotheca floor penetrated by a central funnel-shaped
transverse to decidedly rounded. In stems with hydropore, directed upwards. Margin with a pair
single pairs of hydrothecae the pairs separated by of broad opposite lateral lobes, adcauline wall
a narrow intemodal neck; when more than one thickened and recurved into a cusp; operculum
pair on intemode, these closely adpressed, delicate, of 2 valves. Perisarc of stems and
slightly overlapping, adcauline hydrothccal wall hydrotheca thick, thinning to hydrothccal margin.
overlapping base of that above; free adcauline llydranth with about 16 tentacles on a short,
wall short, convex; abcauline wall complexly wrinkled column, no caecum. Gonothcca large,
curved to almost straight; basal abcauline wall of arising from hydrorhiza on a moderately long
first pair of group with pronounced lateral cylindrical pedicel; barrel-shaped, widest about
swelling, base of higher pairs acutely rounded, middle; body with 6-8 deep annular corrugations,
fitting into intemode. apex transverse, truncate, with thickened rim.
HYDROIDS FROM SOUTHERN QUEENSLAND 343
Gonophore slender, cigar-shaped containing Sertularella Gray, 1848
numerous small ova. Colour, honey-brown.
Sertularella minuscula Billard
Distribution. Circumglobal in tropical waters.
Figure 3A-E
Previously recorded from tropical Australia.
Sertiiiarella minuscula Billard, 1924b; 648.—
Remarks. The annular corrugations on the
Billard, 1925: 139.—Leloup, 1932: 161.—Pennycuik,
gonothecae are usually not all the same depth
1959: 195.—Hirohito, 1974: 18.—Cooke, 1975:98.
around the body, tending to become shallower on
Material examined. Palm Beach, Queensland, 2 km off¬
one side. In the present material there is no sub¬
shore, depth 5-15 m, NMV F91289, small fertile
marginal abcauline intrathecal perisarcal thicken¬
colony on test of a solitary ascidian, alcohol preserved.
ing as described in specimens from Darwin (Wat¬
son, 2000), the colonies being more like those Description. Stolon tubular, rugose; stems to 5
reported from the Houtman Abrolhos Is (Watson, mm high, unbranched, lower stem of same
1997). In most hydrothecae a strand of tissue diameter as stolon, proximal intemode athecate,
infested with numerous large ovoid diatoms stem thereafter thecate, intemodes with 2
extends from the hydranth along the inner alternate hydrothecae, nodes distinct, oblique,
abcauline wall of the hydrotheca towards the mar¬ sloping alternately left and right, usually a small
gin. Hehellopsis scandens is a common epizoite tumescence above and below node.
of the colonies. Hydrothecae on both stolon and caulus, all of
Figure 3. A-E, Sertularella minuscula Billard, 1924. A, stolon with single hydrothecae and erect thecate stem;
B, hydrothecate stem intemodes; C, anterior view of hydrotheca with operculum; D, lateral view of hydrotheca and
operculum; E, female gonotheca. Scale bar: A, 1 mm; C, D, 0.1 mm; B, E, 0.5 mm.
344 J. E. WATSON
same shape. Stolonal hydrothecae widely spaced,
on a short pedicel, cauline hydrothecae sessile,
displaced slightly towards front of stem;
hydrotheca tubular, narrowing slightly to margin,
adcauline wall convex, about half free of inter¬
node, abcauline wall contiguous with border of
intemode, almost straight to weakly concave;
floor of hydrotheca transverse to intemodal axis;
margin quadrangular (anterior view), rim with 4
cusps, lateral cusps sharp with deep semicircular
embayment between, operculum of four fragile
triangular valves. Hydranth with 10-12 tentacles;
no evidence of an abcauline caecum in contracted
or extended hydranths. Gonotheca irregularly
obovoid, usually widening distally, body deeply
crumpled, some gonothecae with 1 or 2 deep
flanges, body narrowing into a rather wide,
smooth pedicel, some arising from within stolonal
hydrothecae, apex of gonotheca a short inverted
funnel, orifice circular. An oval body in 1
gonotheca may be an ovum. Perisarc rather thin,
fragile at hydrothecal margin, operculum and
gonotheca. Colour, colony pale yellowish-white.
Distribution. Indonesia, Caribbean, Microne¬
sia, Japan and Queensland.
Remarks. The species is remarkable for its Figure 4. A, B, Symplecloscyphus sibogae (Billard,
small size and delicacy and the crumpled appear¬ 1924). A, part of stem; B, hydrotheca. Scale bar; A, 1
ance of the gonotheca. mm, B, 0.5 mm.
Symplectoscyplius
smooth throughout; opercular valves thick.
Marktanner-Tumeretscher, 1890 Colour white.
Syniplectoscyphiis sibogae (Billard)
Distribution. This is the second record of the
Figure 4A, B species, the original record being from the type
locality in Indonesia.
Symplecloscyphii.'! sibogae Billard, 1924; 69.—
Billard. 1925; 166.—Vervoort. 1993; 241. Remarks. Although the small colony is obviously
juvenile, it nevertheless conforms to descriptions
Material examined Palm Beach, Queensland, 2 km off¬
shore, depth 5-15 m, NMV F91295, infertile stem of the species. Because of their position below the
detached from substrate, malinol mounted microslide embayments the marginal cusps are rather diffi¬
preparation. cult to see. The species is notable for its smooth
perisarc, and large, elegant hydrothecae with
Description. Stolon thick-walled, tubular. Stem 4
great length free of the intemode,
mm high, straight, with 5 alternate hydrothecae,
an indistinct transverse basal node between
hydrorhiza and first hydrotheca; no other obvious
nodes. Hydrothecac large, tubular, arching out¬ Syntheciidae Marktanner-Tumeretscher, 1890
wards from stem, narrowing to margin, adnate Synthecium Allman, 1872
adcauline wall short, parallel with intemode, free
adcauline wall weakly convex to almost straight, Synthecium campylocarpum Allman
abcauline wall contiguous with border of inter¬ Figure 5A-C
node, faintly concave; floor of hydrotheca nar¬
row, transverse to intemodal axis. Margin everted Synthecium campylocarpum Allman, 1888; 78.—
Marktanner-Tumeretscher, 1890; 248.—Farquhar,
with 3 fairly sharp cusps with shallow embay-
1896; 466.—Stechow, 1913; 127.—Jaderholm, 1919;
ments between; a large internal submarginal cusp
14.—Totton, 1930; 169.—Ralph, 1958; 347.—
at base of each embayment; operculum of 3
Yamada, 1959; 52.—Hirohito, 1969; 18.—Watson,
delicate triangular valves. Perisarc thick and 1996; 78.—Watson, 2000; 40.
HYDROIDS FROM SOUTHERN QUEENSLAND 345
Figure 5. A-C, Synthecium campylocarptim Allman, 1888. A, whole stem: B, hydrothecate hydrocladial inter-
nodes; C. hydrotheca showing regrowth of margin from within hydrotheca. D, Hincksella cylindrica (Bale, 1888).
Part of stem. E-F, AnIennelUi secundaria (Gmelin, 1791). E, fertile hydrocladium; F, female gonotheea (after
Watson. 2000). Scale bar: A, 2.5 mm; E. I mm; B, D, F, 0.5 mm; C, 0.1 mm.
Material examined. Palm Beach, Queensland, 2 km off¬ Hydrothecae paired, opposite, tubular, of same
shore, depth 5-15, NMV F91900, three short, infertile diameter throughout length, supported on a short
stems on calcareous bryozoan. conical section of intemode between pairs;
adcauline walls in contact or slightly separated on
Description. Hydrorhiza thick, tubular. Longest
intemode, adnate walls parallel to intemode,
stem 12 mm high, straight, hydrocladia opposite,
straight, or slightly convex, free wall convex or
three widely separated pairs almost perpendicular
continuing bend of adnate wall, abcauline wall
to axis of stem; stem inlernodes long, cylindrical,
sinuous, basally convex, concave behind margin;
smooth, nodes transverse, just above hydrocladia,
floor of hydrotheca convex, thickened, a hydro¬
a subpposite pair ofhydrotheca between, halfway
pore at base of abcauline wall. Margin faintly sin¬
along some intemodes. Hydrocladia inserted on
uous (lateral view), tilted upwards to intemode,
short, tubular apophyses narrowing distally but
rim slightly but sharply outrolled, many margins
without obvious distal node.
346 J. E. WATSON
regenerated by growth of new hydrotheea from Remarks. Hincksella cylindrica is an uncommon
deep within old, abcauline wall of new species, usually found as single stems or colonies
hydrotheca free, visible, adcauline wall attached consisting of only a few stems.
to wall of primary hydrotheca. Hydranth with
about 12 long tentacles. Perisarc of stem, hydro- Halopterididae Millard, 1962
cladia and hydrothecae thick and smooth, thinner
on hydrothecal margin. Colour, pale yellow. Antennella Allman, 1877
Antennella secundaria (Gmelin, 1791)
Distribution. Type locality. New South Wales
(Allman, 1888). Tropical northern Australia and Figure 5E-F
New South Wales. Previously recorded from
Sertidaria secundaria GmcVm. 1791: 3856.
southern Queensland as S. patiilum by Pennycuik
Aglaophenia .secundaria.—Lamouroiix, 1824: 19.
(1959).
Antennella .ver(/;i(/on(7.—Pennycuik. 1959: 176.—
Remarks. The distinction between Synthecium Watson. 1973: 183.—Millard, 1975: 332.—Ryland and
campylocarpum and S. patulum (Busk, 1852) vvas Gibbons, 1991: 525.—Ramil and Vervoort, 1992: 143.
discussed by Watson (2000). The present material —Mcdel and Vervoort, 1995; 35.—Watson. 1996;
78.—Schuchert, 1997: 14.—Calder. 1997: 29 (full syn¬
is assigned to S. campylocarpum because of the
onymy).—Watson. 1997: 522.—Watson, 2()0(): 45.
shorter hydrothecae, less pronounced marginal
Anienella secundaria.—Stechow and Muller, 1923:
sinuosity of the hydrotheca and yellow colour of 473.
the colony.
Material examined. Palm Beach. Queensland, 2 km off¬
shore. depth 5-15 m, NMV F91290, fertile colonics on
Hincksella Billard, 1918
barnacles and solitary ascidians in crevices, alcohol
Hincksella cylindrica (Bale) preserved.
Figure 5D Description. Stems (hydrocladia) simple,
unbranched, to 6 mm high, arising from a tubular
Serliilarclla cylindrica Bale, 1888; 765. stolon; proximal part of hydrocladium with one to
Synthecium cylindricum.—Ritchie, 1911: 847.—
three athecate intemodes, nodes transverse, each
Stechow. 1923: 150.—Fraser. 1948:234.
intemode bearing one or two nematothecae, dis-
Hincksella cylindrica.—Blackburn, 1937: 173.—
Pennycuik. 1959: 189.—Vervoort. 1959: 245.— talmost node strongly oblique. Intemodes there¬
Vervoort.1968: 101.—Millard, 1975; 232.—Watson, after alternately thecate and athecate, proximal
1979; 234.—Calder, 1993; 68.—Veivoort, 1993: node of thccate intemode strongly oblique, pass¬
193.—Watson and Meinnes. 1999: 108. ing beneath hydrotheca, distal node transverse
below hydrothecal margin.
Material e.xamined. Palm Beach, Queensland, 2 km off¬
shore, depth 5-15 m, NMV F91901, several infertile Hydrotheca occupying almost entire intemode,
stems detached from substrate, malinol mounted facing forward, deep cup-shaped, walls almost
microslide preparation. parallel, free adcauline wall straight to slightly
concave, adnate part convex, curving back to
Description. Stems fragile, to 4 mm high, proxi¬
small hydropore at base of abcauline wall; margin
mal part of stem athecate, upper stem with up to 6
circular, slightly sinuous. Nematothecae bithala-
hydrothecae, stem intemodes wide, cylindrical,
mic, small, 2 on athecate intemode, basal cham¬
curved, smooth, an indistinct slightly oblique
ber stout, cup small, foreshortened on adcauline
node below some hydrothecae. Hydrothecae sub¬
side; mesial inferior stout, adcauline side of cup
opposite to alternate, cylindrical, adnate
foreshortened, just reaching base of hydrotheca,
adcauline wall convex, free adcauline wall about
lateral nematotheca borne on a long, slender pedi¬
one quarter length of adnate wall, continuing
cel where adcauline wall of hydrotheca becomes
curve of fused wall, abcauline wall concave; floor
free, cup broad and shallow, excavated on
of hydrotheca transverse to intemode, narrow.
adcauline side, not quite reaching hydrothecal
Margin circular, rim weakly outrolled. Perisarc of
margin; a small mesial superior nematotheca
lower stem thick, thinning markedly on hydrothe-
inserted beneath hydrotheea. Female gonothecac
eae, most of which have collapsed in mounting.
obovoid, somewhat flattened, facing forward,
Colour, white.
borne on a short, thick pedicel beside mesial infe¬
Distribution. Type locality. Port Jackson, New rior nematotheca; 2 large nematothecae at base;
South Wales (Bale, 1888). Southern Australia, basal chamber of nematotheca long, cup wide,
Pacific coast of North America, Caribbean. shallow, excavated on side facing gonolheca. Ori¬
Previously recorded from southern Queensland. fice of gonolheca distal, subcircular, closed by a