Ecteinascidia maxima Kott, 1985

Kott, Patricia, 2006, Observations on non-didemnid ascidians from Australian waters (1), Journal of Natural History 40 (3 - 4), pp. 169-234: 212-216

publication ID

http://doi.org/ 10.1080/00222930600621601

persistent identifier

http://treatment.plazi.org/id/011D87C1-FFDF-CD72-1FBF-FC96E19CFE2C

treatment provided by

Felipe

scientific name

Ecteinascidia maxima Kott, 1985
status

 

Ecteinascidia maxima Kott, 1985  

Ecteinascidia maxima Kott, 1985, p 93   .

Distribution

Previously recorded (see Kott 1985): Lord Howe I. New record: Queensland (Noosa Heads, 8–10 m, QM G308786)   .

Remarks

The newly recorded colony from the mid-eastern coast of Australia is the only one outside the type locality. The specimens are similar to the type material. Zooids are robust, with large blotches of red colour around the anterior part of the zooid, including bands of colour around the base of each protruding siphon, relatively long siphons, about 15–20 rows of stigmata and an almost continuous coat of transverse muscles on each side of the body   .

Microgastra granosa ( Sluiter, 1904)  

Ascidia granosa Sliuiter 1904, p 36   .

Microgastra granosa: Kott 1998, p 163   and synonymy.

Distribution

Previously recorded (see Kott 1998): Queensland ( Low Is , Bowen , Townsville , Innisfail , Princess Charlotte Bay , Gordonvale ); Indonesia, Japan. New records: Tasmanian Canyons (Ling Hole, 174 m); Queensland (14.685 –18.755 ° S, to 66 m) GoogleMaps   .

Description

The largest newly recorded specimen is 10 cm long. As usual, the sandy test is thin, flaccid to brittle with some sandy, irregular tags from the posterior end of the body. The newly recorded specimens range from relatively short, cylindrical bodies to long, narrow ones about 1 cm diameter and 10 cm long. The branchial siphon is terminal and the atrial is two-thirds of the way down the body. About 50 single branchial tentacles are short and well-spaced and the dorsal membrane is double. That part of the body wall containing the dorsal tubercle and ganglion and ciliated funnel-like openings of the branches of the neural duct (opening along the body wall behind the branchial sac) is closely attached to the test. The body wall is thin, diaphanous, transparent, closely applied to the test. Parallel transverse muscles forming an almost continuous coat are along the right but muscles were not detected on the left side of the body. In the branchial sac are many rows of short stigmata with papillae on the transverse vessels about every two or three stigmata. Internal longitudinal vessels were not detected in the larger specimens. The prepharyngeal groove loops across to the right in front of the dorsal tubercle creating a dorsal fold in the branchial sac. The small gut loop lies embedded in an outgrowth of the body wall that is constricted off from the rest of the body. The stomach is small and oval with internal longitudinal folds. The post-pyloric part of the gut loop is flat and forms a tight primary loop, with the distal end of the gut folded back to the descending limb to form a secondary loop. The gonads are in external pouches of the body wall embedded in the test. The testis, consisting of small crowded follicles, is on the left about one-third of the body length from its posterior end. The ovarian sac associated with a seminal vesicle is embedded in the test of the posterior rim of the atrial opening. The vas deferens, embedded in the test, extends posteriorly from its origin halfway down the testis and loops around its posterior margin before extending anteriorly to the atrial aperture.

Remarks

This is a remarkable species, its body held in place by the parts of it (along the dorsal midline and around the gonads) that are embedded in the test. It is the thin, sand-strengthened test that protects both the gonads and the neural elements of the individual. The filtering area is large but the gut loop is small and entirely evaginated from the body wall in a tight nucleus, presumably held in place between the inflated pharynx and the test. The species has much in common with Ascidia scaevola   , which has a similar sandy test, a branchial fold, compact, flattened gut loop and thin body wall closely adhering to the test. These two species also occupy similar sea-floor habitats and have a similar geographic range from temperate and tropical waters (although A. scaevola   has not been recorded from Japan).

In a survey extending from north of Cooktown (14.5 ° S) to Broad Sound (about 22 ° S), the species was taken at 12 stations (of a total of 383). It was one of the best represented sea-floor species of ascidians in this region, 30 specimens having been taken at one of the stations. Polycarpa chinensis   , P. decipiens   , and P. obscura   are the only species taken in similar numbers at any one station. The record from the temperate water of the Tasmanian Canyons (174 m) is unusual, being the only time the species is recorded outside the tropics, except for the Japanese record. Apparently it has a wide range both north and south of tropical waters.

Cnemidocarpa areolata ( Heller, 1878)  

Styela areolata Heller 1878, p 26   .

Cnemidocarpa areolata: Kott 1985, p 122   and synonymy; Monniot and Monniot 1984, p 577.

Cnemidocarpa irene: Nishikawa 1991, p 96   .

Distribution

Previously recorded (see Monniot and Monniot 1984; Kott 1985; Nishikawa 1991): Western Australia (Dampier Archipelago, Cape Jaubert, NW Cape, Port Hedland, Carnarvon, Shark Bay, Cockburn Sound, Albany); South Australia (Spencer Gulf); Victoria (Bass Strait); New South Wales (Port Hacking, Long Reef); Queensland (Moreton Bay, Capricorn Group, Low Isles); Northern Territory (Darwin); Palau Is, Philippines, Noumea, New Caledonia, Marianas Is, Japan, Fiji, South China Sea, Japan, Sri Lanka. New record: Queensland (18.845 ° S, 146.795 ° E, 26 m)

Remarks

Monniot and Monniot (1984) examined material from Heller’s type locality, Sri Lanka, and found it agreed with the type specimen of Styela areolata Heller, 1878   , in having a deeply curved gut loop and about 12 openings of the short vas deferens on the surface of the ovary. Nishikawa (1991) found three to four similar openings in some from Japan but never as many as the Sri Lanka specimens. As a consequence, these authors proposed that C. irene ( Hartmeyer, 1906)   from Japan (with C. valborgi Hartmeyer, 1919   and C. irma Hartmeyer, 1927   from northwestern Australia as junior synonyms) was distinct from C. areolata Heller, 1878   from Sri Lanka. Specimens assigned to this species by Kott (1985) from Australian locations (Heron Is, Cockburn Sound, South Australia) have been reexamined together with specimens from Fiji and the South China Sea (see Kott 1981; Kott and Goodbody 1982). In all the specimens examined the general morphology is similar, the vas deferens of each gonad opens by a single simple opening on top of the oviducal opening and multiple openings were not detected.

Nevertheless in view of Nishikawa’s (1991) reports of openings of the male duct similar to those in the Sri Lanka specimen, albeit not so numerous, it appears that the openings of the male duct are sometimes subdivided in this species. At this stage, it appears that such subdivision may be the result of intra-specific variation rather than an indication of speciation.

Cnemidocarpa completa Kott, 1985  

Cnemidocarpa completa Kott 1985, p 124   .

Distribution

Previously recorded (see Kott 1985): Victoria (Deal I., Bass Strait); New South Wales (Arrawarra). New record: Tasmania ( Port Davey , Bathurst Channel, 3–37 m, SAM E2879–81 View Materials )   .

Description

The newly recorded specimens were attached to clumps of Pyura irregularis   on a vertical rock wall. The individuals are conical with terminal branchial apertures and atrial apertures on short siphons halfway down the dorsum. The test is thin and flexible, encrusted with sand on the upper half, which has a warty appearance, the lower half being smooth and rounded. On the left are three to six gonads. Sometimes the anterior one divides and both branches continue around the pole of the gut loop. Seven to nine gonads are on the right. The body wall is thin and the branchial sac and gut, gonads, and endocarps are as previously described.

Remarks

The new record confirms the temperate range of this species, which previously was known from Bass Strait to Arrawarra on the central New South Wales coast.

Cnemidocarpa radicosa ( Herdman, 1882)  

Styela radicosa Herdman 1882, p 163   .

Cnemidocarpa radicosa: Kott 1985, p 136   and synonymy.

Distribution

Previously recorded (see Kott 1985): Western Australia (Cockburn Sound); South Australia (St Vincent Gulf); Tasmania (Bruny I. and western and southern coast); Victoria (Bass Strait, Port Phillip Bay )   ; New South Wales (Port Kembla, Port Jackson ); Queensland (Tallebudgera). New records   : South Australia ( Kangaroo I., 10–12 m, SAM E3286 View Materials )   , Tasmania (Bass Strait, 60 m, QM G308810; Port Davey , 3–18 m, SAM E2882–5 View Materials ; Banks Strait)   ; New South Wales (Bass Point—near Wollongong).

Description

Individuals are upright, the posterior two-thirds expanded into an almost spherical posterodorsal swelling. The short atrial siphon projects laterally from where the postero-dorsal swelling narrows abruptly to an anterior cone with a terminal branchial aperture. The test is thin, flaccid, and wrinkled, but tough, posteriorly produced into root-like projections that may form a bulbous holdfast entangled with sand and shell. The body wall is muscular and only loosely attached to the test. The prebranchial area is narrow and the dorsal tubercle has a horizontal S-shaped slit. The dorsal lamina is wide and smooth-edged. Up to 19 internal longitudinal vessels are on the folds and five between the folds. Two gonads are on the left, the posterior one in the secondary gut loop is almost spherical. Like the anterior gonad on the left, the four or five on the right are sausage-shaped. Gut and gonads are embedded in the body wall, which is thickened across the posterior part of the body.

Remarks

The external shape of the individuals of this species and their wrinkled, tough test resembles that of Cnemidocarpa pedata ( Herdman, 1881)   in which gonads may also be firmly embedded in the test, but which is distinguished by the lack of posterior thickening of the body wall, having instead numerous small upright endocarps in the loop of the gut and between the long, branched gonads. Cnemidocarpa stolonifera   is another robust species with a similar body shape, although it has deep furrows and grooves rather than wrinkles in the test. It has similar gonads to C. pedata   but its apertures are on siphons marked by four deep parallel grooves and they originate close to one another on the anterior part of the body. The siphons of both C. pedata   and the present species are separated by at least onethird of the body length. Kott (1985) found that C. stolonifera   was distinguished from C. pedata   also by its longer stomach and rectum and more numerous stigmata in each mesh.

Cnemidocarpa radicosa   has a range around the southern half of the continent, from Cockburn Sound in the west to the Queensland – New South Wales border.

QM

Queensland Museum

SAM

South African Museum

Kingdom

Animalia

Phylum

Chordata

Class

Ascidiacea

Order

Phlebobranchia

Family

Perophoridae

Genus

Ecteinascidia

Loc

Ecteinascidia maxima Kott, 1985

Kott, Patricia 2006
2006
Loc

Microgastra granosa:

Kott P 1998: 163
1998
Loc

Cnemidocarpa irene:

Nishikawa T 1991: 96
1991
Loc

Ecteinascidia maxima

Kott P 1985: 93
1985
Loc

Cnemidocarpa areolata:

Kott P 1985: 122
Monniot C & Monniot F 1984: 577
1985
Loc

Cnemidocarpa completa

Kott P 1985: 124
1985
Loc

Cnemidocarpa radicosa: Kott 1985 , p 136

Kott P 1985: 136
1985
Loc

Styela radicosa

Herdman WA 1882: 163
1882
Loc

Styela areolata

Heller C 1878: 26
1878