Bijdragen tot de Dierkunde, 54 (2): 231-242—1984

Serehyba sanctisebastiani n. gen., n. sp.

(, Tubulariidae), symbiont of a gorgonian octocoral from the southeast coast of Brazil

by

Fabio Land da Silveira

Dept. de Zoologia da Universidade de Säo Paulo, Cx. Postai 20520, Sào Paulo, SP, 01498, Brazil

&

Alvaro Esteves Migotto

Centro de Biologia Marinha da Universidade de Sào Paulo, Cx. Postai 83, Sào Sebastiäo, SP, 11600, Brazil

The is referable Summary species to a new ,

the basis of Serehyba, on a gonosome structure An athecate hydrozoan, Serehyba sanctisebastiani, represent- the of comparable to siphosome some Siphono- a new is described. It with ing genus, possesses gonosomes the is "cormidium" in- cormidium-like tubulariids: phora: gonosome a a structure unique among a

set branched and the distal of nematophores and a proximal cluding a "gonodendron" a "siphon";

gonodendron. S. sanctisebastiani is apparently transitional detached anthomedusae of the gonophores are between the families Tubulariidae and Corymorphidae. It reduced and the symmetrical type nematophore is a symbiont ofthe gorgonian octocoral Lophogorgiapunicea ( = "siphon") is a "palpon". It differs from (Milne Edwards & Haime, 1857). in the previously designated genera family ac-

cording to Petersen from the Résumé (1979): solitary Tubularia with firm Linnaeus, 1758, a perisarc

On décrit un Hydrozoaire athèque, Serehyba sanctisebastiani, and from the solitary Zyzzysus Stechow, 1921, d’un Celui-ci des représentant genre nouveau. possède with thin a perisarc, by being colonial; and cormidium gonosomes ayant une structure rappelantun et from the colonial L. les Tubulariides: Ectopleura Agassiz, 1862, by qui est unique parmi une garniture

radial canals in the and distale de nématophores ramifiés et un gonodendron having hydranth

S. sanctisebastiani fait la transition proximal. apparemment separate endodermis canals within parenchyma entre les familles des Tubulariidae et des Corymorphidae. in the hydrocaulus. C’est un symbionte de la Gorgone Lophogorgia punicea Hydroid polyps of the family Tubulariidae (Milne Edwards & Haime, 1857). from are poorly known the southeast coast of

Brazil. The only record is of the hydranth of the

INTRODUCTION medusa of Ectopleura dumortieri (Van Beneden,

1844) from the lagoon region of Cananéia,

A and of athecate State of Sâo Paulo, Brazil new genus species an hydroid (Vannuci, 1957).

of the family Tubulariidae Allman, 1864, was

da found near the Centro de Biologia Marinha

Universidade de Sâo Paulo (CEBIMar-USP) DESCRIPTION

and Baleeiro the on Jarobâ Point Point, at

south continental of Sâo Sebastiâo sanctisebastiani margin Serehyba n. gen., n. sp. State of Sâo Brazil. We have Channel, Paulo, (Figs. 1-4)

found this be always hydroid to epibiotic on

Material examined. — Brazil, State ofSäo Paulo, Säo Lophogorgia punicea (Milne Edwards & Haime, Sebastiâo, Jarobâ and Baleeiro Points (20°45'42"S

- ■ 1857) = indet. b 1961: 10 F. ( Lophogorgia sp. Bayer, 45°26'30~W), July 1981, 5 m, 1 hydranth, L. da

64 VII 212, text-fig. d-f, pl. fig. 2). Silveira coll.; 28 August 1981, 5 m, 1 hydranth, F. L. da

Downloaded from Brill.com10/04/2021 08:36:00AM via free access - SP. 232 F. L. DA SILVEIRA & A. E. MIGOTTO SEREHYBA SANCTISEBASTIANI N. G., N.

3.5 4 F. the of the Silveira coll.; 19 September 1982, m, hydranths, Sebastiâo, geographic designation

L. da Silveira coll.; 4 November 1982, 4 m, 11 hydranths, and is transformed into the study area, genitive A. E. Migotto coll. of singular a Latin masculin noun.

maintained in In the laboratory, specimens were

between 22 and aquaria at water temperatures varying

fresh nearshore 28°C. The hydranths were fed daily with GENERAL FEATURES OF COLONIES (TROPHO-

hand-towed by a plankton plankton organisms captured SOMES)

All were net (60 [im mesh). gross anatomy measurements A of data done with fixed and preserved . Living colors are comprehensive account quantitative

Colores" referred to color charts in "Atlas de los (Küp- from several animals is summarized in table I.

The nomenclature employed for pers, 1979). nematocysts The attached its hydrozoan grows closely to is that of Weill (1937) and Millard (1975). Histological ex- host of gorgonian by means a hydrocaulus ex- of and were done with aminations trophosomes gonosomes tension which is next to the axis skeleton and specimens fixed in Bouin's and Heidenhain's fixatives. under the of the The Histological examinations of free medusae were done with coenenchyme gorgonian.

formalin. Sections stained with specimens fixed in were hydrozoan projects outward and off the host. Mallory Tricromie after counterstaining cell nuclei with One the total of largest animals had a Weigert's Hematoxylin (Mahoney, 1973). Mean surface of 150 of which 95 hydrocaulus mm, mm Point length water temperature at Jarobâ was 24°C (max. 28°C;

was invested with min. 20°C) and salinity ranged from 31 to 34%M for the gorgonian coenenchyme.

period March 1981 — February 1983.

Museu de da Holotype: MZUSP-479, Zoologia TABLE I

Universidade de Sâo Paulo, Brazil, State of Sào Paulo,

character variation ofSerehybasanctisebastiani Sâo Sebastiâo, Jarobâ Point (20°45'42~S 45°26'30~W), 4 Morphological

based measurements of twelve animals. November 4 1 and of n. n. sp., on 1982, m, hydranth part Lophogorgia gen., well-formed Immature forms = hydranths without punicea (Milne Edwards & Haime, 1857), A. E. Migotto

forms = with well-formed coll. medusae; mature hydranths

medusae. Paratypes: MZUSP-478, 19 September 1982, 4 m, 1

female hydranth, F. L. da Silveira coll.; MZUSP-480, 4

sections in November 1982, 4 m, longitudinal histological Immature forms Mature forms

preparations, 1 female hydranth, A. E. Migotto coll.; fur- average (range) average (range) in the thermore, five paratypes are deposited Zoölogisch

coll. ZMA Coel. 8375-8376. Museum, Amsterdam, no. Hydrocauli

diameter (mm) 0.9 (0.7 - 1.0) 1.5 (1.0 - 2.0)

number of canals* 10 (9 - 11) 10 (10 - 11)

— colo- Diagnosis: Trophosome solitary or neck length (mm) 1.5 (0.7 - 2.0) 4.0 (1.0-7.5) without nial, rooting processes. Hydrocaulus Hydranths

diameter 2.0 - 4.0 - 5.0) with firm perisarc, the central space filled with (mm)** (1.7 2.4) (2.5

- 3.0 (2.0 - 4.0) 6.0 9.0) and with length (mm)*** (4.0 parenchyma longitudinal separate en- Tentacles dodermal canals. Modular construction of aboral ( = proximal) in cormidium including gonoden- gonosome number 26 (18 - 27) 30 (28 - 34) and released free- dron - - palpon. Gonophores as length (mm) 5.0 (4.0 6.0) 15.0 (6.0 20.0)

swimming reduced medusae. Medusae radially oral ( = distal)

number 44 (34 - 48) 60 (55 - 71) symmetrical, with four radial canals and ring length (mm) 1.2 (1.0 - 1.5) 2.0 (1.5 - 4.0) canal, without tentacles or tentacle buds and Gonosomes

without nematocysts in the exumbrella. number 11 (8 - 13) 11 (8 - 16)

- length (mm) 0.5 (0.3 - 0.6) 3.5 (2.5 5.0)

Medusae — The is derived Etymology: genus name length (mm) — 1.1 (1.0 - 1.2) from the language of the Brazilian In- Tupi, diameter (mm) — 0.85 (0.8 - 0.9)

dians, meaning "mangrove-tree" (ciri = crab;

is = and transformed into the yba tree) * of the at about 50 mm from the base hydranth of nominative a Latin feminine noun. ** singular at the level of the aboral tentacles

*** is from the base the the The specific name derived from Sâo to top of hypostome

Downloaded from Brill.com10/04/2021 08:36:00AM via free access 54 - 1984 233 BIJDRAGEN TOT DE DIERKUNDE, (2)

Fig. 1. Large size hydranth drawn from life. AT, aboral tentacles; G, gonophore(mature medusa); H, hydrocaulus; N,

nematophore (palpon); OT, oral tentacles. Scale 2 mm.

the of the Coenenchyme growth occurs over the skeleton. At top projecting hydrocauli

there of hydrocaulus without the development of the are hydranths various sizes (figs. 1 and

The is continuous sheet gorgonian axis skeleton. The stem of the 2). coenosarc a under

of uniform diameter for the and central filled hydranth was except perisarc possesses a space

the with and divided two transverse constrictions; stalk distal to parenchyma by complete or the constrictions broader than was slightly incomplete longitudinal gastrovascular canals

3A and The is average diameter. The hydrocaulus is sur- (figs. 3B). coenosarc delicately rounded membranous and naked main axis of the stalk. by a smooth, striped parallel to the

Transverse sections of the 5 perisarc. The stem is light yellow (Noo A70 hydrocaulus at mm

intervals showed that the M[o). On larger animals the distal limit of the near hydranth the

free the base central is with perisarc next to the coenosarc and cavity bordered longitudinal en- of the six dodermal The rise hydranth possesses up to transverse ridges (fig. 3A). ridges give annulations. of the canals which increase in number and in Exposed parts hydrocaulus to vary

diameter from the may be overgrown with fleshy filamentous red away hydranth (lig. 3B).

white with algae. Hydrocaulus length appears to vary ac- Living hydranths are an orange

the of the axis around the mouth and cording to length gorgonian ring (Noo Ago M70) a

Downloaded from Brill.com10/04/2021 08:36:00AM via free access 234 - F. L. DA SILVEIRA & A. E. MIGOTTO SEREHYBA SANCTISEBASTIANI N. G., N. SP.

Fig. 2. Lateral aboral view of large size hydranth drawn from life. AT, aboral tentacles;

G, gonophore (mature medusae); H, hydrocaulus; N, nematophore (palpon). Scale

2 mm.

reddish-brown ring (N20 A70 Mßo) around the face of the hypostome. The gonosomes on large base of the aboral tentacles. The junction be- animals are well developed in size and number,

is aboral tentacles Their tween the stem and the trophosome a con- hanging among (fig. 2).

stalks branched the second order. The striction devoid of perisarc and is the point of are to

branches rise the flexing movements. At the base of the hydranth proximal give to gonophores there is circlet of filamentous branches defensive in- a evenly-spaced (medusae) and distal are aboral tentacles which flattened dividuals armed are proximally, (nematophores) with

2 On forms solid, pointed and whitish in color. Distally nematocysts (figs. and 4). young

the few and with there is a crown of three or four concentric ir- gonosomes are reduced, only regular circlets of tight, short, whitish, filamen- nematophores. The nematophores are milky tous oral tentacles (fig. 1). The hypostome is white and cauliflower-like, while gonophores cone-shaped, starting at the base of the aboral are orange to red and bell-shaped in early stages tentacles and narrowing at the mouth. (fig. 4).

The following characteristics refer to at-

tached terminal maturing stages and to newly GENERAL FEATURES OF GONOSOMES bell- released medusae. Medusae are deep

Medium-sized animals ir- than to large possess shaped (length slightly larger diameter),

the lower without tentacles regular circlets of gonosomes on sur- transparent and or tentacle

Downloaded from Brill.com10/04/2021 08:36:00AM via free access - 235 BIJDRAGEN TOT DE DIERKUNDE, 54 (2) 1984

Oral tentacles:

— 16.5 11.0 - Large stenotele, x 13.0 x 7.5

[xm. Few.

— Small - 7.5 5.0 stenotele, 8.0 x 6.0 x [im.

Numerous. Capsule oval, butt about half of

capsule length.

— Heterotrichous anisorhiza, 14.0 x 7.5- 12.5

8.5 x [Jim. Capsule subspherical. Rare.

Fig. 3. Cross sections of the hydrocaulus of the largest Aboral tentacles: polyp drawn from preserved specimen. A, distal

— 12.5 11.0-11.0 8.0 hydrocaulus; B, proximal hydrocaulus; ep, epidermis; en, Large stenotele, x x endodermis; gc, gastrovascular canal; pr, parenchyma. Numerous. [Am.

Same scale as fig. 4. — Small 8.0 6.0 - 7.0 4.5 stenotele, x x jxm.

Numerous. Capsule oval, butt about one buds. There four radial canals and are a ring third length of capsule.

canal dotted with orange to red pigment. The

manubrium is as long as the umbrella or slight-

ly shorter, dull and the color of the radial

canals. There the are no nematocyst tracts on bell of the medusa. Hours before release,

medusae show coordinated and variable con-

tractions of the bells. The medusae are poor

4. Gonosome drawn from Fig. (cormidium) preserved Fig. 5. Nematocysts, left to right: desmoneme, large specimen. S, stalk; G, gonophore (medusa); N, stenotele and heterotrichous anisorhiza. Scale 10 μm. nematophore (palpon). Scale 1 mm.

remain — Heterotrichous anisorhiza, 18.5 x 12.0 swimmers and have a tendency to on

-14.0 10.5 Numerous. the bottom. We tried to maintain newly releas- x (xm. Capsule ed medusae in small vials to which fresh subspherical.

— 8.0 - added from time time. Desmoneme, x 5.5 6.5 x 4.0 plankton was to They fjim. survived Numerous. oval, thread two days, never feeding, suggesting Capsule discharged that the mouth did with five coils. not open.

Nematophore: NEMATOCYSTS

— 15.0 13.0 - 13.5 12.0 Stenotele, x x [xm.

Few. butt almost The nematocysts are of three types (fig. 5), Capsule oval, halflength of distributed as follows: capsule.

Downloaded from Brill.com10/04/2021 08:36:00AM via free access 236 F. L. DA SILVEIRA & A. E. MIGOTTO - SEREHYBA SANCTISEBASTIANI N. G., N. SP.

Fig. 6. Photomicrograph of diagonal section through base of hydranth and distal part of

hydrocaulus to show the fenestrae. E, epidermis; F, fenestrae; G, gastrodermis; CGH,

of gastrovascular cavity hydrocaulus; M, mesoglea; MC, myocytes; PC, parenchymatous

cushion; (100 x ).

Fig. 7. Photomicrograph ofhydranth body wall sectioned at the base to show the endoder-

mal sphincter. E, epidermis; G, gastrodermis; M, mesoglea; MBS, myocyte bundles of

sphincter; (400 x ).

Downloaded from Brill.com10/04/2021 08:36:00AM via free access 54 - 1984 237 BIJDRAGEN TOT DE DIERKUNDE, (2)

Fig. 8. Photomicrograph of hydranth body wall sectioned Fig. 9. Photomicrograph of hydranth body wall sectioned

the base of aboral tentacle show the endoder- above the aboral tentacle show the at crown to crown to gonosome mis canals. E, epidermis; G, gastrodermis; GBC, stalk. E, epidermis; EG, early gonophore; G, gastroder-

blind canals; P, x mis; GCG, of gastrodermal parenchyma; (334 ). gastrovascular cavity gonosome; M,

mesoglea; MD, medusa; (50 x ).

— Heterotrichous 14.0 11.0 distal is anisorhiza, x part of the neck there a short cone of en-

of -12.0 x 10.0 [Jim. Numerous. Capsule dodermis, the wall which is interrupted by

subspherical. longitudinal openings (fenestrae) that connect

the internal cavities of the hydranth with the

these slits there is stem (fig. 6). Bordering a MICROSCOPIC ANATOMY of the there thickening mesoglea and are

Transverse sections of hydrocauli showed that clusters of myocytes (fig. 6). the endodermal the base of the and longitudinal canals are only In hydranth just distal to and the central is filled with the cavity parenchyma constriction region are numerous myocytes.

become (fig. 3). The coenosarc epidermis possesses scat- Radial myocytes in the epidermis

almost absent delicate radial bundles tered nematocysts. Myocytes are upon contraction, and in and but increase endodermis form the epidermis gastrodermis, myocytes a strong circular closer the base of the At the neck fenestrated of to hydranth. sphincter (fig. 7). The cone en- region myocytes are rather common, forming a dodermis progresses as a cylinder that enlarges mesh mainly in the epidermis; epidermal to a funnel merging with the polyp wall. The

cells tall funnel and the make the floor of the secretory are replaced by supporting cylinder up cells and nematoblasts. The amount of gastrovascular cavity. The wall of the

increases. Invested the most makes the mesoglea also on hypostome, up to the mouth, up roof

Downloaded from Brill.com10/04/2021 08:36:00AM via free access 238 - F. L. DA SILVEIRA & A. E. MIGOTTO SEREHYBA SANCTISEBASTIANI N. G., N. SP.

of Beneath the floor is whorl of filiform the gastrovascular cavity. one oral tentacles; the

a closed that circles the base of the from the surface of the space gonosomes develop

hydranth, the parenchymatous cushion (fig. 6). hypostome between the two whorls of tentacles;

Parenchyma of this cushion is evenly separated erect stem with firm perisarc which reaches to

from gastrodermis by mesoglea. Gastrodermal the base of the hydranth body. The histology of

folds occur on the floor of the gastrovascular the trophosome combines most features of

the of which the cavity, crests represent regular tubulariid polyps with an elaborate structure of

inward of the tentacles. the stem the of progress proximal by presence separate

blind canals short endodermal canals within the Peripheral radiate for a longitudinal

distance between the aboral tentacles which is found in (fig. 8). parenchyma, a feature always

The enclosed parenchyma of the cushion is large size solitary hydranths of the family Cory-

separated from the parenchyma of the tentacles morphidae Allman, 1867 (subfamilies Cory-

by a thin lamella. Some endodermis cells within morphinae and Branchiocerianthinae Rees,

the tentacles are myocytes placed at right angles 1957), and which has been retained by the

to the main axis of the tentacle. Epidermal solitary tubulariid Zyzzyzus solitarius (Warren,

of the myocytes tentacles are parallel to the 1906). Millard (1975) supposed that Zyzzyzus

main axis. The of the intermediate between gastrodermis hypostome represents an stage early

is much crested and uneven. The epidermis is Corymorphidae and Tubulariidae. Millard

in with Rees that the also crested a regular radial pattern agreed (1957) Tubulariidae

unrelated the mentioned above. the to patterns evolved from members of Corymorphidae.

The oral tentacles outward found endodermal are simple pro- Grönberg (1897) separate

of the canals in distal of the of the jections hypostome body wall, filled with parts hydrocaulus

parenchyma which is separated from the solitary Tubularia indivisa Linnaeus, 1758.

thin lamella. The Watson described and gastrodermis by a gonosomes (1980) a new genus

are hollow body wall outgrowths (figs. 9 and species of a rare colonial tubulariid, Ralpharia

10). In the endodermis of nematophores magnifica, with longitudinal canals within the

cells distal The secretory are less abundant than in other hydrocaulus stem. colony structure

of the of and of S. sanctisebastiani regions gonosome (fig. 11). Hydranths Ralpharia magnifica

are dioecious, without dimorphism of probably refutes the assumption that the

Male elaborate of endodermal gonophores. medusae were recognized as structure separate

canals is feature forms free-swimming stages. The manubrium epider- a of solitary only, being

mis of male mature medusae was filled with an acquisition some solitary Tubulariidae share

distributed We with their It evenly spermatozoans. found Corymorphidae ancestors. follows

few of male cells. that in the of S. sanctisebastiani the remnants early stage germ hydranth

of radial canals Mature female medusae remain attached. presence immediately above the

and cushion be related Oogonia occur at the surface layer oocytes parenchymatous may not to

in the of the elaboration of occur deeper layer manubrium an solitary large-sized forms

epidermis. derived from the Corymorphidae. Rees (1957)

emphasized the presence of radial canals to

devise the evolutionary lineage of solitary DISCUSSION hydranths starting with the Corymorphidae; he

external of the drew between the radial The anatomy trophosome of a homology canals of

sanctisebastiani the Serehyba agrees with diagnostic the solitary polyps of Branchiocerianthus imperator

features of the hydrozoan athecate family Miyajima, 1900, with those of Tubularia indivisa

Tubulariidae (Kühn, 1913; Kramp, 1949; to explain that the float of Pelagohydra mirabilis

Rees, 1957; Naumov, 1960; Brinckmann-Voss, Dendy, 1902 (family Margelopsidae Uchida,

is the basal half of 1970; Millard, 1975; Petersen, 1979): hydranth 1927) a solitary pelagic

with one whorl of filiform aboral tentacles and hydranth.

Downloaded from Brill.com10/04/2021 08:36:00AM via free access - 239 BIJDRAGEN TOT DE DIERKUNDE, 54 (2) 1984

10. of sectioned oral-aboral axis of Fig. Photomicrograph gonosome along trophosome:

is the and left side is the distal of aboral right side proximal part onegonosome. AT, ten-

tacle (sectioned along longest axis); dn, distal part of nematophore; EG, early gonophore;

MD, medusa; N, nematophore; OT, oral tentacle (sectioned along transversal axis);

(40 X ).

The of the of S. and 1940 "does structure gonosomes sanc- of Myriothela capensis Manton, tisebastiani is tubulariids unique among possess- not communicate with that of the blastostyle, a

sides ing "modular" construction (sensu Chapman & layer of mesoglea, covered on both by en-

Stebbing, 1980). To understand their organiza- doderm, spanning the tentacle base". tion draw with the of The of S. sanctisebastiani we an analogy siphosome gonosomes are more

the is than the some Siphonophora: gonosome a "cor- complex gonophore-producing

and of other tubulariids. The fact that midium" including a "gonodendron" a blastostyles

the detached the differentiate earlier than the "siphon"; gonophores are re- nematophores duced anthomedusae and the nematophore gonophores during development (see observa-

= is tions of ( "siphon") a "palpon" (Garstang, 1946). living material below) shows the dif-

In with the cormidium of ferent nature of the and comparison gonosomes blastostyles.

the of Siphonophora, the order of gonodendron and Among genera Tubulariidae, hydroids

is inverted: is with fixed = fixed siphon gonodendron proximal to gonophores ( sporosacs) are

of considered be distinct palpon. We do not think that the gonosomes to from hydroids with

S. sanctisebastiani with the free medusae are comparable (Rees, 1957; Naumov, 1960;

of other athecate blastostyles some hydrozoans Brinckmann-Voss, 1970; Millard, 1975). Fixed

M. The all medusoid (e.g. Myriothela Sars, 1815). sporosacs are degenerate stages, nematophores of S. sanctisebastiani differ in their including the eumedusoid, cryptomedusoid,

and from the heteromedusoid and structure development tentacles of styloid stages (originally the blastostyles of Myriothela. Manton (1940) defined by Kühn, 1913 and retained by observed that the lumen of the tentacles of the Hyman, 1940; Naumov, 1960; Campbell, blastostyles of Myriothela penola Manton, 1940 1974; Millard, 1975). Brinckmann-Voss (1970)

Downloaded from Brill.com10/04/2021 08:36:00AM via free access 240 - F. L. DA SILVEIRA & A. E. MIGOTTO SEREHYBA SANCTISEBASTIANI N. G., N. SP

of of shown in Fig. 11. Photomicrograph part nematophore fig. 10. Note the simple ar-

chitecture and lack of secretory cells in the endodermis of the distal parts of the

distal of nematophore; dn, parts nematophores; G, gastrodermis; gen, gastrovascular

of cells of cavity nematophore; n, nematocysts; NS, nematophore stalk; se, secretory en-

dodermis; (400 X ).

and Millard the with fixed of the (1975) distinguished genera Agassiz, 1862) or gonophores

Zyzzyzus Stechow, 1921 and Tubularia Linnaeus, asymmetrical type, and the colonial Ectopleura

with fixed from the with firm free 1758, sporosacs, genera Ec- a perisarc and producing either

L. 1862 and L. medusae topleura Agassiz, Hybocodon (genus Ectopleura L. Aggassiz, 1862) or

with free medusae. Agassiz, 1862, with fixed gonophores of the symmetrical type.

Watson described fifth sanctisebastiani (1980) a genus, Serehyba n. gen., n. sp. represents

reduced and Ralpharia, with free-swimming a colonial tubulariid with a firm perisarc

medusae (four rudimentary marginal tentacles with the gonosome in cormidium.

of and no mouth) the symmetrical type. The

main diagnostic character which distinguishes BIOLOGICAL NOTES Ralpharia from Ectopleura is the absence of

tracks the exumbrella of the In the that from time nematocyst on laboratory we observed to

medusa (Watson, 1980: 54). time the hydranths of Serehyba sanctisebastiani

We with agree Petersen (1979) that the regressed and desintegrated at the level of the

of offers of hydroid stage tubulariids good margin the perisarc of the hydrocauli, follow-

systematic characteristics on which distinction ed by replacement by regenerating buds (figs.

be the B among genera can based. Therefore, 12A, and C). The bud regenerated a

level classification of tubulariid in- in in the in genus polyps hydranth only one day same way as

the with cludes solitary Zyzzyzus a thin perisarc the related palma Torrey, 1902 (see and tuber-like attachment of hydrocaulus, the Torrey, 1910) and C. nutans Sars, 1835 (see

with Tubularia a firm and solitary perisarc pro- Svoboda, 1973). We also observed a double-

L. ducing either free medusae (genus Hybocodon regenerating bud and the formationof two new

Downloaded from Brill.com10/04/2021 08:36:00AM via free access - 241 BIJDRAGEN TOT DE DIERKUNDE, 54 (2) 1984

and timing that pertain to the association be-

S. anctiseb and there tween s astiani the gorgonian,

both are possible benefits to species: Lophogorgia

for the provides a strong support hydrozoan,

which its and grows hydrocaulus very fast;

linear extension of the smooth perisarc of S.

sanctisebastiani allows gorgonian coenenchyme

additional trend growth over substratum (a

known for other gorgonians, cf. Kinzie, 1970;

24°C. Silveira Van which would Fig. 12. Regenerating stages drawn from life at A, & 't Hof, 1977),

regeneration bud 53 hours after purposeful amputa- slow early hasten the usually development of the oc- tion; B, early differentiation of regenerating fields of tocoral. hydranth and hydrocaulus 72 hours after amputation; C,

early differentiation of oral tentacles and budding of

80 hours after aboral gonosomes amputation; at, tentacles; ACKNOWLEDGEMENTS oral g, early gonosome bud; hy, hypostome; ot, tentacles;

T, gorgonian branch tip. Scale 1 mm. We are grateful to Dr. S. Stancyk for his critical reviews of

the manuscript and helpful suggestions. We thank Dr. E.

Schlenz for helping with the German literature. Further-

more, we are indebted to Dr. F. M. Bayer and Mr. C. B. the site of hydranths at purposeful amputation Castro for classification of the gorgonian coral.

of a polyp. The gonosome development of

regenerating individuals stopped with differen- LITERATURE tiation of the nematophores and incomplete budding of gonophores in the shape of fingerlike ALLMAN, G. J., 1864. On the construction and limitation

of the Ann. blastostyles. The regeneration and replacement genera among Hydroida. Mag. nat. Hist., (3) 13: 345-380. of the be hydranths through autolyses may a BAYER, F. M., 1961. The shallow-water Octocorallia of histophysiological rejuvenation of the hydranth the West Indian region. A manual for marine

a stimulus of the (Tardent, 1963) or growth biologists. Stud. Fauna Curaçao, 12 (55): [i-viii], hydrocaulus (Hughes, 1983). 1-373, pis. I-XXVII. BRINCKMANN-VOSS, A., 1970. Anthomedusae/Athecatae

(Hydrozoa, ) of the Mediterranean, I. Close relationships between tubulariids and . Fauna Flora Golfo Napoli, 39: [i-îïi], their invertebrate hosts have been noted for 1-96, pis. I-XI. unicus with 1902), Cnidaria. Hybocodon (Browne, CAMPBELL, R. D., 1974. In: A. C. GIESE & hydrorhiza branching within the sponge J. S. PEARSE eds., Reproduction of marine in-

I. Acoelomate and Hymeniacedon perlevis (Montagu) (see Millard, vertebrates, pseudocoelomate

metazoans: 133-199 (Academic Press, New York & 1975), and Zyzzyzus solitarius (Warren, 1906) London). from South with tubers Africa, fleshy storage CHAPMAN, G. & A. R. D. STEBBINC, 1980. The modular and rootlets within silicious supporting habit a In: P. TARDENT & sponges recurring strategy. R. (Warren, 1906; Millard, 1975). There is at least TARDENT eds., Development and cellular biology of

of coelenterates: 157-162 Holland one record a solitary tubulariid, Tubularia (Elsevier/North Biomedical Press, Amsterdam). multitentaculata Fraser, 1938, living on FRASER, O. M., 1938. Hydroids of the 1934 Allan unspecified gorgonians off the coast of Lower Hancock Pacific Expedition. Allan Hancock Pacif. California (Fraser, 1938). Ralpharia magnifica Exped., 4 (1): 1-105. tubular embedded in the presents a hydrorhiza GARSTANG, W., 1946. The morphology and relations of

of membranaceum the Siphonophora. Quart. microsc. Sci., 87: sheet-like mass Parerythropodium J. 103-193. Kükenthal, 1906 (Anthozoa, Alcyonacea) and 1897. Kenntniss der GRÖNBERG, G., Beiträge zur Gattung the actinulae able which are to grow pedicels Tubularia. Zool. Jb., (Anat.) 11 (1): 61-76, pis. 4-5. the penetrate alcyonacean (Watson, 1980). HUGHES, R. G., 1983. The life-history of Tubularia

Although we do not yet know the conditions indivisa (Hydrozoa: Tubulariidae) with observations

Downloaded from Brill.com10/04/2021 08:36:00AM via free access 242 - F. L. DA SILVEIRA & A. E. MIGOTTO SEREHYBA SANCTISEBASTIANI N. G., N. SP

the of T. on status ceratogyne. J. mar. biol. Ass. REES, W. J., 1957. Evolutionary trends in the classifica-

U.K., 63 (2): 467-479. tion of capitate hydroids and medusae. Bull. Br.

HYMAN, L. H., 1940. The invertebrates: Protozoa Mus. nat. Hist. Zool., 4 (9): 453-534, pis. 12-13.

i-x, 1-726 'T through Ctenophora, 1: (MacGraw- SILVEIRA, F. LANG DA & T. VAN HOF, 1977. Regenera-

Hill, New York). tion in the gorgonian Plexaura flexuosa (Cnidaria,

KINZIE, R. A., 1970. The ecology of the gorgonians Octocorallia). Bijdr. Dierk., 47 (1): 98-108.

(Cnidaria, Octocorallia) of Discovery Bay, Jamaica: SVOBODA, A., 1973. Underwater observations on the life

1-107 (Ph. D. thesis, Yale University). cycle of Corymorpha nutans (Hydrozoa). Helgo-

KRAMP, P. L., 1949. Origin of the hydroid family länder wiss. Meeresunters., 24: 145-150.

Corymorphidae. Vidensk. Meddr. dansk naturh. TARDENT, P., 1963. Regeneration in the Hydrozoa.

Foren., Ill: 183-215. Biol. Rev., 38 (3): 293-333.

KÜHN, A., 1913. Entwicklungsgeschichte und Verwandt- TORREY, H. E., 1910. Biological studies on Cory-

schaftsbeziehungen der Hydrozoen, I. Die Hy- morpha, III. Regeneration of hydranth and hold-

droiden. Ergebn. Fortschr. Zool., 4: 1-284. fast. Univ. Calif. Pubis. Zool., 6 (10): 205-221.

KÜPPERS, H., 1979. Atlas de los colores. Translation by VANNUCI, M., 1957. On Brazilian hydromedusae and

Feliz de la Fuente: 1-161 (Editorial Blume, Barce- their distribution in relation to different water

lona). masses. Bolm. Inst. Oceanogr. S. Paulo, 7 (1-2):

MAHONEY, R., 1973. Laboratory techniques in zoology 40-41.

269-270 1906. On Tubularia solitaria (Butterworth & Co., London). WARREN, E., sp. nov., a

MANTON, S. M., 1940. On two new species of the hydroid from the Natal Coast. Ann. Natal. Mus.,

hydroid Myriothela. Scient. Rep. Br. Grahamld. 1: 83-96, pis. X-XI.

Exped., 1: 255-293. WATSON, J. E., 1980. The identity of two tubularian

MILLARD, N. A. H., 1975. Monograph on the Hydroida hydroids from Australia with a description and

of southern Africa. Ann. S. Afr. Mus., 68: 1-513. observations on the reproduction of Ralpharia

Mem. Mus. NAUMOV, D. V., 1960. Hydroids and Hydromedusae of magnifica gen. et sp. nov. natn.

the marine, brackish and freshwater basins of the Vict., 41: 53-63.

U.S.S.R. Opred. Faune SSSR, 70: 1-585. (In WEILL, R., 1937. Contribution à l'étude des Pteronemida

Russian; translated by Israel Program for Scientific (Hydrozoaires). Le cnidome de Cladocoryne fioccosa

Translations, 1969.) Rotsch et son interprétation (d'après les documents

K. 1979. in In: laissés feu Maurice Bull. Inst. PETERSEN, W., Coloniality Hydrozoa. par Philbert).

G. 719: 1-11. E. LARWOOD & B. R. ROSEN eds., Biology and océanogr. Monaco,

systematics ofcolonial organisms: 105-140 (Academic

Press, London).

First draft received: 18 May 1984

Final version received: 17 August 1984

Downloaded from Brill.com10/04/2021 08:36:00AM via free access