Antennella aff. quadriaurita Ritchie, 1909

Galea, Horia R., 2013, New additions to the shallow-water hydroids (Cnidaria: Hydrozoa) of the French Lesser Antilles: Martinique, Zootaxa 3686 (1), pp. 1-50 : 29-30

publication ID

https://dx.doi.org/10.11646/zootaxa.3686.1.1

publication LSID

lsid:zoobank.org:pub:17A93C58-F09C-484A-A26A-F4F27BC91A6C

DOI

https://doi.org/10.5281/zenodo.5263649

persistent identifier

https://treatment.plazi.org/id/D6410C37-BF57-FFE8-FF36-FD31FB05FAD0

treatment provided by

Plazi

scientific name

Antennella aff. quadriaurita Ritchie, 1909
status

 

Antennella aff. quadriaurita Ritchie, 1909

(Fig. 7 K–N)

Material examined. Stn. 8, 27.i.2012, 9– 15 m, M076: fertile (female) colony on Thyroscyphus marginatus ( Allman, 1877) . Additional material for comparison: Tristan da Cunha group, Inaccessible Island, Stn 7. I10, 28.xi. 2007, HRG-0341: several sterile stems.

Remarks. Compared to the material from Inaccessible Island studied earlier by myself ( Galea 2010 b), the present specimens have smaller hydrothecae, the lateral nematothecae of the anterior pair are shorter (compare Fig. 7 M 1 and M 2), and the ahydrothecate segments bear 3 or 4 nematothecae in two parallel, closely set rows (Fig. 7 K), instead of only one, occasionally two.

The cnidome of the Caribbean material is composed of three types of capsules (Fig. 7 N 1): 1) seed-shaped microbasic heteronemes, ca. 4.2 × 2.6 µm, occurring rarely in the coenosarc; 2) small, banana-shaped microbasic mastigophores, ca. 6.4 × 2.2 µm, abundant in the tentacles, also scattered in the coenosarc; 3) large, ovoid microbasic heteronemes with thick shaft (pseudostenoteles?), (14.1 –16.0)×(5.6–6.4) µm, occurring in the nematophores, also scattered in the coenosarc.

In contrast, the large microbasic heteronemes in material from Inaccessible Island are smaller, slender, and more tubular [(11.2–12.5)×(3.8 –4.0) µm], and their shaft is less conspicuous (Fig. 7 N 2).

Given: 1) the extreme variability in size of the stems and the number of hydrothecae they carry [from 1.4 cm high and 9 hydrothecae in Ritchie's (1909) material from Gough Island, to up to 6 cm high and 40 hydrothecae in the Indian specimens studied by Leloup (1932)]; 2) the shape (walls parallel or divergent) and size of the hydrothecae; 3) the shape of the upper chamber of the first pair of lateral nematothecae (see variation in Schuchert 1997); 4) the varied number of nematothecae (from 1 to 4) carried by the ahydrothecate segments (Millard 1977); 5) the lack of data on the cnidome composition in nearly all the previous records from around the world; 6) the lack of knowledge on the nature of the gonophores,

I raise the question of the specific limitation in A. quadriaurita , and I refrain from including with certainty the present material in the synonymy of this species, pending a broader study based on specimens from various localities around the world.

Geographical distribution. Likely unsettled at present, though a summary of the world records is given by Schuchert (1997); to this, it should be added a recent record from Brazil ( Grohmann et al. 2003). In the Caribbean, the species was found in Cuba ( Stechow 1919 a 8), Belize ( Spracklin 1982), and Martinique (present study).

- small, seed-shaped heteronemes ca. 4.0× 2.6 ca. 4.2 × 2.6 ca. 3.5 × 2.4 not found, but likely

present - large heteronemes (gonophore) (9.6 –12.0)×(2.9–3.2) absent absent absent