Escharella Gray, 1848

Reverter-Gil, Oscar & Souto, Javier, 2015, Redescription of some species of Bryozoa described by J. Jullien and L. Calvet in the NE Atlantic, European Journal of Taxonomy 157, pp. 1-17 : 11-13

Genus Escharella Gray, 1848

Escharella guernei ( Jullien & Calvet, 1903) comb. nov.

Fig. 6 A–D; Table 3

Smittia guernei Jullien & Calvet, 1903: 103 , pl. 13, fig. 1.

Escharella pseudopunctata Souto, Fernández-Pulpeiro & Reverter-Gil, 2007: 368 , figs 3–4.

? Mucronella peachi – d’Hondt 1974: 30 (not Johnston, 1847).

Material Examined

Lectotype of Smittia guernei (here designated)

SPAIN: Hirondelle st. 56, 43°38’30’’ N, 06°08’16’’ W, NW Iberian Peninsula, 90 m, 4 Aug. 1886, Jullien coll., originally labeled as “ Smittia deguernei J. Jullien ” ( MOM INV- 22518).

Holotype of Escharella pseudopunctata

FRANCE: English Channel , Pourquoi Pas? st. 101, Jun. 1914 ( MNHN 20063 ).

Paratypes of Escharella pseudopunctata

FRANCE: same data as holotype ( MNHN 20064).

Other material examined

SPAIN: Thalassa st. W403, 43º56.2’ N, 5º39.3’ W, Avilés Canyon, N Iberian Peninsula, 280–650 m, 10 Oct. 1970, det. d’Hondt, labeled as “ Mucronella peachi (?)” ( MNHN 7069); same data as preceding, species not marked on original label ( MNHN 7070).

Diagnosis

Colony encrusting unilaminar, multiserial. Zooids hexagonal to oval,with smooth, slightly convex frontal. Pores do not perforate, as tubules run from pores to margins of zooid. Secondary orifice campanulate. Primary orifice with small, quadrangular lyrula and small, rounded condyles. Six distal spines, retained in ovicellate zooids. Avicularia not present. Ovicell globular, recumbent on distal autozooid.

Remarks

Smittia guernei was described by Jullien & Calvet (1903) for two samples collected off the NW coast of the Iberian Peninsula at a depth of 90 m. In the collections of MOM there are two slides, labeled as types of S. deguernei [sic!], collected at the same station, but only one of them (MOM INV-22518) matches the original description and figure of the species, and it is therefore designated here as the lectotype. The other specimen (MOM INV-22580) corresponds to P. amoena comb. nov. (see above).

Smittia guernei does not seem to have been reported under that name since its original description. Reverter-Gil & Fernández-Pulpeiro (2001) reviewed the original record, without studying the original material, and stated that the species probably belongs in Escharella . The species was reported by d’Hondt (1974) as “ Mucronella peachi ?” from a Thalassa locality at the Avilés Canyon, N Iberian Peninsula (see Material examined section).

Recently, Souto et al. (2007) described a new species, Escharella pseudopunctata , from material collected in the English Channel at an unrecorded depth. Examination of the lectotype of S. guernei reveals that E. pseudopunctata is actually a junior synonym. For a complete description of the species and further discussion of its generic assignment see Souto et al. (2007: 368–371).

There are some minor differences between the types of S. guernei and E. pseudopunctata . In the former, the ovicell is globular, recumbent on the distal autozooid ( Fig. 6C ), but in the latter the ovicell is almost entirely immersed in the distal autozooid (see Souto et al. 2007: fig. 4a, c). However, in the Thalassa material the ovicell may be recumbent or immersed in the same colony; this is rather frequent in several other genera of cheilostomatous Bryozoa (A. Ostrovsky, pers. comm. May 2015). Moreover, the secondary orifice seems more markedly bell-shaped in E. pseudopunctata ( Fig. 6D ; see also Souto et al. 2007: fig. 3d–e). Finally, zooids of E. pseudopunctata are slightly larger than those of S. guernei .

Escharella guernei comb. nov. was collected off the northern Iberian Peninsula at a depth of 90 m and at an unrecorded depth between 280 and 650 m, as well as from an unrecorded locality in the English Channel.

Figures

Fig. 6. Escharella guernei (Jullien & Calvet, 1903) comb. nov. A. Autozooids (MOM INV-22518, lectotype). B. Same, primary orifice. C. Same, ovicellate zooids. D. Ovicellate and non-ovicellate zooids; note the ovicells, recumbent or immersed (MNHN 7069).