Styraconyx sargassi Thulin, 1942

Kaczmarek, Łukasz, Bartels, Paul J., Roszkowska, Milena & Nelson, Diane R., 2015, The Zoogeography of Marine Tardigrada, Zootaxa 4037 (1), pp. 1-189 : 110-111

117. Styraconyx sargassi Thulin, 1942

Bathyechiniscus tetronyx G. Steiner, 1926 ( Marcus 1936)

Bathyechiniscus tetronyx G. Steiner ( Mathews 1938)

Styraconyx sargassi n. sp. ( Thulin 1942)

Bathyechiniscus tetronnyx G. Steiner 1926 ( Rodriguez-Roda 1947, 1952) Bathyechiniscus tetronyx Steiner, 1926 ( Chitwood 1951)

Styraconyx sargassi ( Renaud-Mornant 1979a)

Terra typica : Atlantic Ocean (Azores)

Atlantic Ocean:

• 43°4′N, 31°W [43°04′N, 31°00′W]; [FAO27] Type Locality: Undefined locality, N of Azores, floating Sargassum . Marcus (1936), Thulin (1942), Du Bois-Reymond Marcus (1960), Kristensen & Higgins (1984a)

• (?) 27°57′N, 97°01′W; 4 ft bsl / 0 m bsl: [FAO31] USA, Texas State, Aransas County, Gulf of Mexico, near Rockport, Aransas Bay, Mud Island. Chitwood (1951), Renaud-Mornant (1967b)

• (?) 28°04′N, 96°51′W; 4 ft bsl / 0 m bsl: [FAO31] USA, Texas State, Aransas County, Gulf of Mexico, near Rockport, Cedar Bayou, sample from Sargassum (brown alga). Chitwood (1951), Renaud-Mornant (1967b)

Balearic Sea:

• (?) 41°35′N, 02°33′E; 0 m bsl: [FAO37] Spain, N oriental coast of Spain, Barcelona Province, Arenys de Mar, a small breakwater (protected part), almost superficial rocks, cement blocks and gravel, marine algae.

Rodriguez-Roda (1947, 1952), Renaud-Mornant (1967b)

• (?) 39°54′N, 03°05′E; 0 bsl: [FAO37] Spain, Balearic Islands, Majorca, Pollença Municipality, Port de Pollença. Rodriguez-Roda (1947, 1952), Renaud-Mornant (1967b)

• (?) 38°36′N, 00°03′W; 0 bsl: [FAO37] Spain, Alicante Porvince, Altea. Rodriguez-Roda (1947, 1952), Renaud-Mornant (1967b)

Indian Ocean:

• (?) 23°23′S, 43°38′E; 0 m bsl: [FAO51] Republic of Madagascar, Toliara Province, Toliara, Mozambique Channel, great reef, stations 1F, 3F–5F and 10F, coralline sand. Renaud-Mornant (1979a)

Pacific Ocean:

• 36°42′N, 121°49′W: [FAO77] Undefined locality, USA, California State, California coast, in washings from the brown alga Dictyota . Mathews (1938)

Record numbers (Sea/Ocean classification): Atlantic Ocean: 1(3?), Balearic Sea: 3?, Indian Ocean: 1?, Pacific Ocean: 1; total: 8(6?).

Record numbers (FAO classification): FAO27: 1, FAO31: 2?, FAO37: 3?, FAO51: 1?, FAO77: 1; total: 8(6?).

Remarks: This nominal species of the sargassi group has a long history of taxonomic confusion and misidentification (for more details see Kristensen & Higgins 1984a). At present, it is not possible to determine which records belong to this species and which do not. Kristensen & Higgins (1984a) suggested that this species may be restricted to algal associations and that specimens from other substrates should be examined very carefully. Additionally, the same authors rejected the suggestion by Renaud-Mornant (1967b) that the Chitwood (1951) specimens (marked as Bathyechiniscus tetronyx, Chitwood 1954 , p. 325) from the Gulf of Mexico belong to S. sargassi . Rather, Kristensen & Higgins (1984a) stated that the Chitwood specimens are neither of these species, but probably belong to two different taxa. For the purposes of this paper we have included these records but identified them with bracketed question marks as it is not clear to which species they should be attributed. According to Kristensen & Higgins (1984a), the only records that are most likely to belong to S. sargassi are those of Rodriguez-Roda (1947, 1952) and Matthews 1938. In conclusion, and in agreement with Kristensen & Higgins (1984a), only the specimens from California and the type locality should be considered as valid, while other localities need confirmation.