NOTES 



A SECOND RECORD OF A RARE 



SIPHONOPHORE EPIBULIA RITTERIANA 



HAECKEL 1888 



During a survey by the National Marine Fish- 

 eries Service research vessel David Starr Jordan, 

 a siphonophore, Epibulia ritteriana Haeckel, of 

 the family Epibuliidae, was collected in a neuston 

 haul on July 10, 1971, at 0225 to 0246 hr, PST, 

 in the northeast Pacific Ocean at lat 37°20'N, 

 long 135°00'W. The only other record of this 

 species was one specimen, described by Haeckel 

 (1888), collected off Ceylon in 1882 during the 

 Challenger Expedition. Evidence of the world- 

 wide distribution is typical of most species of 

 siphonophores, 



Haeckel's identification was refuted by Totton 

 and Bargmann (1965) who stated several rea- 

 sons for their disagreement, the most important 

 being that Haeckel had described a ring of pal- 

 pons under the float which they said was a char- 

 acter not typical of the suborder Cystonectae. 

 Totton and Bargmann (1965) stated further 

 that the suborder included only the families Phy- 

 salidae and Rhizophysidae; the Epibuliidae were 

 considered "species inquirendae." They con- 

 cluded that Haeckel's description was based on 

 "an incompletely examined specimen of Athor- 

 ybia rosacea," and "that Haeckel's figure is un- 

 realistic and idealized though beautifully exe- 

 cuted," and in their opinion, "if such animals 

 existed no doubt one will be found again." They 

 also disagreed with unillustrated descriptions of 

 two species of Epibuliidae, one Rhyzophysa 

 chamissomis by Eysenhardt (1821) and the 

 other Epibulia erythrophysa by Brandt (1835). 

 It was my good fortune to collect and observe 

 the living cystonect, described and illustrated 

 here, which I have identified as E. ritteriana by 

 reference to Haeckel's drawings and description. 

 Haeckel's specimen is identical with mine, ex- 

 cept that the gastrozoids in his illustration have 

 larger and more conspicuous mouths. I have 

 also collected specimens of Athorybia rosacea, 

 identified by direct observation and comparison 



with drawings by Totton and Bargmann (1965) . 

 Outstanding characters of A. rosacea are the 

 shape of the pneumatophore and large and dis- 

 tinct bracts arranged in several layers. My spe- 

 cimen of E. ritteriana showed no evidence of 

 bracts, nor scars or spaces where bracts could 

 be attached. I believe, therefore, that the two 

 species are not to be confused and that Epibulia- 

 does in fact exist, ergo, the family Epibuliidae. 

 The rarity of records for this family of cysto- 

 nects may be attributed in part to the fact that 

 as surface floating organisms they exist in a 

 stratum seldom sampled by plankton tows be- 

 cause most "net time" is subsurface. 



Description of Epibulia ritteriana 



The complete corm of this Cystonectae is 

 about 25 mm high and 20 mm in diameter, after 

 preserved in 5% solution of formaldehyde (Fig- 

 ure 1). The whole colony presented brilliant 

 shades of pink. The large ovate, almost spheric 

 pneumatophore was coral red (light red) with 

 the apical pore (with a sphincter) surrounded 

 by a purple pigmentation, still visible after pre- 

 servation. The crown of palpons around the 

 float (young gastrozoids) and the siphons (gas- 

 trozoids) appeared rose, and the latter presented 

 a purple spot near the end. Tentacles and ten- 

 tilla were yellowish, the gonodendra bright red 

 and purple. 



The colony appears arranged as follows: 

 pneumatophore and siphosome. The siphosome 

 presents the palpons at the part closer to the 

 pneumatophore, and the siphons at the other end, 

 with the tentacles attached at the base; and the 

 gonodendra distributed between the siphons. 



The pneumatophore or top float is filled with 

 gas, probably carbon monoxide as it is the case 

 in other siphonophores (Pickwell, Barham, and 

 Wilton, 1964). The pneumatophore is an ovate 

 chitinous case, 8 mm x 10 mm in size. Accord- 

 ing to Haeckel (1888) the size of the pneumato- 

 phore ranged from 10 mm x 12 mm in the ex- 

 panded stage to a spheroid of 3 to 4 mm after 



507 



