Schizotheca carmenae, Reverter-Gil & Fernández-Pulpeiro, 2007

Reverter-Gil, Oscar & Fernández-Pulpeiro, Eugenio, 2007, Species of genus Schizotheca Hincks (Bryozoa, Cheilostomata) described in the Atlantic-Mediterranean region, with notes on some species of Parasmittina Osburn, Journal of Natural History 41 (29 - 32), pp. 1929-1953 : 1937-1940

Schizotheca carmenae sp. nov.

( Figure 4A–E )

Strophiella tubigera Jullien, 1903 ?: d’Hondt 1975, p 576.

Material examined

Holotype: MNHN-7426: 38 ° 449N, 28 ° 32.59W. Jean-Charcot, Biaçores, st. 61. 77 m. 14 October 1971.

Other material. MNHN-7519 (with more species): 37 ° 419N, 25 ° 33, 59W. Jean-Charcot, Biaçores, st. 145. 135– 148 m. 30 October 1971. MNHN-7543 (with more species): 37 ° 519N, 25 ° 419W. Jean-Charcot, Biaçores, st. 188. 45 m. 4 November 1971.

Dr Harmelin’s personal collection: ‘‘ Biaçores 1971, st. 167, 130 m, 1 November 1971, 37 ° 469N, 25 ° 48,59W’ ’, and ‘‘S Portugal, Sagres , Grotte Donzelle. PAL 13, Oct. 86’’ .

Etymology

We dedicate this species to our dear colleague and friend Dña. M a Carmen Barcia Leal, who died on 14 May 2004. We will forever remember her comradeship, her unfailing good humour, her capacity to work, and her brave fight against illness.

Description

Colony unilaminar to multilaminar, forming a broad spreading sheet. Autozooids oval to rhomboidal, in alternating series separated by distinct grooves; frontal surface slightly convex, smooth or slightly granular, imperforate except for up to four large, marginal pores (often two).

Primary orifice longer than wide; anter semielliptical, with denticulations small and scarce, that appear to originate from towards the middle of the orifice; poster concave, without sinus, with two small round condyles that delimit an apparent wide, shallow sinus. Peristome well developed, somewhat laminar, with an inconspicuous pseudosinus at the proximal border. Up to six oral spines on the edge of the colony, generally reduced to two to four in calcified zooids, and to two in ovicellate ones.

An adventitious avicularium proximo-laterally to the orifice (occasionally absent; on rare occasions two); mandible wide, triangular, with distal end curved in the form of a beak and orientated laterally; foramen extensive, occupying half to two-thirds of the rostrum; cross bar fine and without columella.

Vicarious avicularia of similar size to the autozooids, situated particularly on the edges of the colony and orientated towards the periphery; structure similar to that of the adventitious avicularia. The vicarious avicularium is less than twice the size of the adventitious avicularium.

Kenozooids irregularly shaped, of similar size or smaller than the autozooids; may bear an adventitious avicularium similar to that in the autozooids.

Ovicell partially immersed by secondary calcification, smooth and imperforate, with a large more or less triangular proximal fissure.

Ancestrula not observed.

Measurements

MNHN-7426 (holotype). AZL: 0.47¡0.03 (20); AZW: 0.35¡0.04 (20); OL: 0.10¡0.005 (20); OW: 0.09¡0.008 (20); OVL: 0.19¡0.01 (3); OVW: 0.24¡0.02 (3); VAL: 0.26¡0.03 (12); VAW: 0.13¡0.02 (12); AAL: 0.15¡0.02 (16); AAW: 0.08¡0.01 (16); VAL/AAL51.73.

Remarks

Schizotheca carmenae sp. nov. is clearly differentiated from other species of the genus by: the form of the orifice, which has a slightly semielliptical anter with few denticulations, poster concave, without sinus and cardella, with two small round condyles that delimit an apparent wide, shallow sinus. The structure of the adventitious and vicarious avicularia is similar, with a wide triangular rostrum with a very extensive, lanceolate foramen and cross bar lacking denticle; the vicarious avicularium is less than twice the size of the adventitious avicularium.

The material ascribed here to S. carmenae sp. nov., originating from the Azores and deposited in the Muséum National d’Histoire Naturelle, had previously been cited as Strophiella tubigera Jullien, 1903 ? [sic] by d’Hondt (1975). Apart from the three original samples we have examined two colonies, given to us by Dr J.-G. Harmelin, originating from the Azores Isles and from SW Portugal (Sagres).

Schizotheca tuberigera (see further below) and S. carmenae are clearly distinguished by several characteristics: amongst others, in S. tuberigera the orifice is orbicular and has two proximal teeth; the avicularia are narrow, with a thick denticle and foramen closed over by calcification; the ovicells are prominent and have a large fissure that narrows at the apex; whereas in S. carmenae the orifice is semielliptical, the avicularia are wider, without denticle and with a very extensive foramen, whereas the ovicell is immersed by calcification and has a wider, shorter fissure.

Schizotheca carmenae likewise shows certain similarities to S. fissa , although they are easily differentiated. The primary orifice in S. fissa is suborbicular, wider than long; the peristome is tubular, well developed, with a median, U-shaped notch; the zooids have six oral spines, reduced to four in ovicellate zooids; the adventitious avicularia are sporadic and associated distally with the ovicells. In S. carmenae , the orifice has a semielliptical anter and is longer than wide; the peristome is less well developed and has a less marked pseudosinus at the proximal edge, the zooids have four to six oral spines, reduced to two in ovicellate zooids. The zooids usually have an adventitious avicularium situated proximo-laterally to the orifice. Finally, the values of all parameters measured are greater in S. carmenae .

Figures

Figure 4. (A–E) Schizotheca carmenae sp. nov.: (A) growing edge of the colony, showing adventitious avicularia (MNHN-7519); (B) growing edge of the colony, showing adventitious and vicarious avicularia (MNHN-7426, holotype); (C) primary orifice (MNHN-7426, holotype); (D) an ovicellate zooid with adventitious avicularia (MNHN-7426, holotype); (E) group of zooids at the growing edge, showing adventitious and vicarious avicularia (Sagres, Portugal, photograph: J.-G. Harmelin). (F, G) Schizotheca buski sp. nov.: (F) general view of the colony, showing two rows made of vicarious avicularia and kenozooids (NHM-1899.7.1.5199, holotype); (G) growing edge of the colony, showing vicarious avicularia (below) and oval adventitious avicularia (left above) (NHM- 1963.4.18.23).