Adeonellopsis aff. multiporosa Aristegui, 1985

Ramalho, Laís V., Rodríguez-Aporta, Raquel & Gofas, Serge, 2022, Preliminary account on the bryozoans of the Alboran platform (Western Mediterranean), with description of two new species, Zootaxa 5094 (1), pp. 53-91 : 71

Adeonellopsis aff. multiporosa Aristegui, 1985

( Fig. 8 )

aff. Adeonellopsis multiporosa Aristegui, 1985: 427 , fig. 3.

Material examined. MNCN 25.03/4297 , MNCN 25.03/4298 : BV12, 112– 120 m; coll. UMA; two living plus two dead fragments, and one living fragment, respectively. MNCN 25.03/4299 : BV13, 95–99 m; coll. UMA; two living and three dead fragments. MNCN 25.03/4300 : BV14, 96–100 m; coll. UMA; eight dead fragments. MNCN 25.03/4301 : BV15, 96 m; coll. UMA; one dead fragment.

Description. Colony erect, rigid, with slender, bilaminar branches ( Fig. 8A ). Zooids elongate, almost rectangular (L/W = 2.45) [L 463–546–607 (N 23, SD 41), W 193–223–249 μm (N 14, SD 18)], arranged around the branch in six to eight longitudinal series, and separated from each other by a deep depression ( Fig. 8B, C ); marginal areolar pores present, variable in size and up to 15 in number ( Fig. 8D ). Primary orifice obscured by a tall, curved peristome ( Fig. 8B ), peristomial aperture wider than long [L 50–61–73 (N 8, SD 7), W 86–97–116 μm (N 8, SD 12)], semi-circular and with a beaded, convex proximal border ( Fig. 8D ). Frontal surface crenulated, with a large central area perforated by 11–20 circular spiraminal pores ( Fig. 8B–D ). Avicularium suboral, drop-shaped, touching the proximal border of the peristome, small [L 63–72–80 μm (N 9, SD 5)], directed distally or slightly obliquely; mandible not curved ( Fig. 8C ). No other avicularia or fertile zooids observed.

Remarks. Aristegui (1985) described Adeonellopsis multiporosa from the Canary Islands (eastern Atlantic). At first sight, specimens from the Alboran platform are very similar to this species, sharing a similar number of zooids per series, the distally or slightly distolaterally directed suboral avicularium of similar size (L 60–90 µm in the Canarian specimens), and absence of interzooidal avicularia. However, there are two main differences between the Canarian and Alboran populations: A. multiporosa has zooids of different shape (L/W: 2 vs 2.45) and also wider (L 550–600, W 250–300 µm), and the spiraminal pores are more numerous (20–25 vs 11–20). We believe these differences not to be significant enough to erect a new species. Therefore, we treat the Alboran platform specimens as A. aff. multiporosa .

Figures

FIGURE 8. Adeonellopsis aff. multiporosa Aristegui, 1985 (MNCN 25.03/4298). A. General view of a colony fragment showing the bifurcation. B. Detail of the branch showing zooids arranged in longitudinal series and the curved distal peristome. C. Close-up of some zooids showing the suboral avicularium and spiraminal pores. D. Detail of a zooid showing the beaded convex proximal margin of the orifice, spiraminal pores, as well as some areolar pores. Scale bars: A, 800 µm; B, 300 µm; C, 200 µm; D, 100 µm.