Protiaropsis anonyma ( Maas, 1905 )

Schuchert, Peter & Collins, Richard, 2021, Hydromedusae observed during night dives in the Gulf Stream, Revue suisse de Zoologie 128 (2), pp. 237-356 : 257-259

publication ID

https://doi.org/ 10.35929/RSZ.0049

publication LSID

lsid:zoobank.org:pub:8382D1CA-7C0E-4B1C-9591-4CEAA2F296FB

DOI

https://doi.org/10.5281/zenodo.5710590

persistent identifier

https://treatment.plazi.org/id/D0118A7C-5B19-0003-FC67-FE46FAC179B8

treatment provided by

Felipe

scientific name

Protiaropsis anonyma ( Maas, 1905 )
status

 

Protiaropsis anonyma ( Maas, 1905) View in CoL View at ENA

Fig. 12 View Fig A-C

Heterotiara anonyma Maas, 1905: 19 View in CoL , pl. 3 figs 19-21. – Bigelow, 1909: 216, pl. 41 figs 12-14. – Vanhöffen, 1911: 211, pls 12-13. – Bigelow, 1918: 382. – Bigelow, 1928: 287. – Russell, 1940: 516, figs 5-7. – Kramp, 1959a: 17, 125, fig. 131. – Kramp, 1961: 122. – Kramp, 1965: 41. – Kramp, 1968: 53, fig. 138. – Schmidt, 1973: 22. – Schmidt & Klinker, 1974: 34. – Bouillon, 1980: 314. – Brinckmann-Voss & Arai, 1989: 41, figs 1b, 1e.

not Heterotiara anonyma View in CoL . – Bigelow, 1913: 25, records North Pacific. [= Bythotiara depressa Naumov, 1960 View in CoL ]

in part Heterotiara anonyma View in CoL . – Arai & Brinckmann-Voss, 1980: 69, fig. 40. [in part Bythotiara depressa Naumov, 1960 View in CoL ]

Protiaropsis anonyma View in CoL . – Stechow, 1919: 150, new combination. – Schuchert, 2010: 338.

? Kanaka pelagica Uchida, 1947: 103 View in CoL , fig. 5. – Kramp, 1961: 123. – Kramp, 1968: 58, fig. 153. – Schmidt, 1973: 22, could be a young Heterotiara anonyma View in CoL . – Bouillon, 1980: 316, could be Heterotiara anonyma View in CoL .

Examined material: BFLA4037 ; 1 specimen; 26 -MAR-2019; size 12 mm high; part preserved in formalin and deposited as UF-013457, small part in alcohol for DNA extraction; 16S sequence MW528657 View Materials .

Observations: Bythotiaridae medusa 12 mm high, bell cylindrical, not compressed laterally, mesoglea thick, especially apical jelly which is about 1/3 of the total bell height; bell margin with regular furrows in which lie the tentacles. Manubrium 2/3 the height of the subumbrella, shaped like inverted cone, section cross-shaped, interradial wall smooth, mouth cruciform, rather small, four red strands run along the interradial corners of the manubrium. Four thin radial canals, no mesenteries; circular canal thin. 10 tentacles, length about half the height of the bell, originating from under circular canals without formation of a distinct tentacle bulb but with an epidermal swelling at the junction of tentacle and circular canal, proximal part of tentacles curving adnate around bell margin in furrows, tapering only slightly distally, ending in bright orange, spherical to ovoid knob, diameter about 0.3 mm. No ocelli.

16S Data: A blastn search in GenBank with the sole 16S ( MW528657 View Materials ) gave mostly species of Filifera / Anthoathecata , but all below 90% identity and thus precluding any conclusions on relationships.

Distribution: Widespread in warm parts of the Atlantic, Indian, and Pacific Oceans, usually in depths of 0 to 600 m ( Arai & Brinckmann-Voss, 1980; corrections in Brinckmann-Voss & Arai, 1989). Type locality: Indonesia, 0.2933°S, 129.2418°E, 0-1000 m depth.

Remarks: Most illustrations of this species do not show the terminal swellings of the tentacles (e.g. in Kramp, 1959a, 1968), a typical character of Bythotiaridae medusae. These are almost invariably lost in specimens caught with a plankton net, but they are normally present in this species (see Kramp, 1948, 1965; Schmidt, 1973; Arai & Brinckmann-Voss, 1980).

The size of the examined medusa was at the lower end of the range usually given for this species (12-20 mm, Maas, 1905; Bigelow, 1909; Vanhöffen, 1911). Bigelow (1918) also found somewhat smaller (up to 13 mm) in the nearby Bermuda region, likewise Bouillon (1980) in animals from Papua New Guinea.

The interradial red strands are rather conspicuous in the living and preserved animal ( Fig. 12 View Fig A-B), but they have been mentioned only rarely so far. Only Vanhöffen (1911) observed them in an animal caught near the Nias Islands ( Indonesia).

The nematocysts have been described by Russell (1940) and Bouillon et al. (1988a). The species has large desmonemes which are typical for the family Bythotiaridae .

The taxonomic scope of Protiaropsis anonyma is not yet fully clear as there are other similar species, some of which which could prove to be conspecific (see also discussions in Schmidt, 1973).

Protiaropsis minor ( Vanhöffen, 1911) is somewhat smaller (6-12 mm), has perhaps a shorter manubrium, and 16 to 24 tentacles (see description by Pagès et al., 1992). Bouillon et al. (1988a) found both morphotypes in sympatry and kept them distinct.

Kanaka pelagica Uchida, 1947 has eight tentacles but is much smaller (1.8 mm). It was based on a single specimen which was likely a juvenile. Kramp (1953) thought it might belong to P. minor , while Schmidt (1973) and Bouillon (1980) think it is referrable to Protiaropsis anonyma .

Gymnogonium zhengzhongii Xu & Huang, 1994 , is small (2.2 mm), has a short manubrium, and a pair of branched radial canals, resulting in six canals in total. The manubrium of the only observed specimen had gonads. Bouillon et al. (2006: 182) thought that it could belong to Protiaropsis anonyma . As the the species is based on a single specimen, it cannot be excluded that the branched radial canals were a developmental aberration. New material has to prove the validity of the species, but as the type specimen was apparently mature at 2.2 mm, the genus and species should be retained as valid for the moment.

Bouillon (1980) thought that also Bythotiara depressa Naumov, 1960 could be conspecific with P. anonyma as he found intermediate forms. Bythotiara depressa differs from P. anonyma in having an irregularly folded surface of the gonads. Brinckmann-Voss & Arai (1989) examined the problem in detail and they worked out diagnostic differences of the two species (see also Xu et al., 2016). Some of the previous records of P. anyonyma from colder waters of the North Pacific Ocean were actually B. depressa .

All these ambiguities underline the need for a comprehensive dataset of 16S DNA barcodes which will hopefully improve the species delimitations.

Kingdom

Animalia

Phylum

Cnidaria

Class

Hydrozoa

Order

Anthoathecata

Family

Bythotiaridae

Genus

Protiaropsis

Loc

Protiaropsis anonyma ( Maas, 1905 )

Schuchert, Peter & Collins, Richard 2021
2021
Loc

Heterotiara anonyma

Arai & Brinckmann-Voss 1980: 69
1980
Loc

Kanaka pelagica

Bouillon J. 1980: 316
Kramp P. L. 1968: 58
Kramp P. L. 1961: 123
Uchida T. 1947: 103
1947
Loc

Protiaropsis anonyma

Schuchert P. 2010: 338
Stechow E. 1919: 150
1919
Loc

Heterotiara anonyma

Bigelow H. B. 1913: 25
1913
Loc

Heterotiara anonyma

Brinckmann-Voss & Arai 1989: 41
Bouillon J. 1980: 314
Schmidt & Klinker 1974: 34
Schmidt H. E. 1973: 22
Kramp P. L. 1968: 53
Kramp P. L. 1965: 41
Kramp P. L. 1961: 122
Kramp P. L. 1959: 17, 125
Russell F. S. 1940: 516
Bigelow H. B. 1928: 287
Vanhoffen E. 1911: 216
Maas O. 1905: 19
1905
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