Adeonella lichenoides ( Lamarck, 1816 )

Taylor, Paul D. & Tan, Shau-Hwai Aileen, 2015, Cheilostome Bryozoa from Penang and Langkawi, Malaysia, European Journal of Taxonomy 149, pp. 1-34 : 17-18

Adeonella lichenoides ( Lamarck, 1816)

Fig. 9 A–G

Eschara lichenoides Lamarck, 1816: 176 .

Adeonella lichenoides – Hayward 1988: 126, figs 1c, 2–3.

Material

MALAYSIA: MSL BRY016, Kampung Kuala Temoyong, Langkawi, found among fishing debris.

Description

Colony erect, rigidly calcified, bushy ( Fig. 9A ), comprising bifurcating, bifoliate, strap-like branches, about 2.2–2.5 mm wide, with approximately a dozen series of zooids across width of branch.Autozooids small, rounded hexagonal, longer than wide, 0.29–0.38 mm long by 0.19–0.24 mm wide, distinct with deep interzooidal grooves, frontal shield convex, a slight umbo sometimes developed centrally, densely granular in surface texture, with large areolar pores covering most of surface; primary orifice more or less equidimensional, about 0.08 mm long, a shallow U-shaped sinus separated from anter by small condyles ( Fig. 9E ); secondary orifice somewhat transversely elliptical, a subcircular spiramen separated from secondary orifice by a calcified bridge in mature zooids ( Fig. 9 F–G). Gonozooids larger than autozooids, with a broad, shallow orifice separated from a wide spiramen by a deep calcified bridge with a process on proximal edge.Adventitious avicularia ( Fig. 9F ) developing on frontal shield of autozooids, often laterally to spiramen but occasionally more proximally, generally one or two per autozooid, sometimes absent, orientated variously; rostrum high gothic arch-shaped; cross-bar uncalcified; opesia rounded, a little wider than rostrum. Vicarious avicularia sporadically distributed ( Fig. 9D ), longer than autozooid, about 0.57 mm long by 0.21 mm wide; rostrum elongate, spatulate with a distal shelf; crossbar uncalcified; opesia roughly semicircular with a sloping cryptocyst-like proximal edge; frontal shield with areolar pores similar to those of autozooids. Kenozooids present along some branch edges.

Remarks

Found among debris discarded from a fishing net, Adeonella lichenoides is the only rigidly erect bryozoan collected in either Langkawi or Penang during the fieldwork in October 2013. This species is distributed throughout the Indo-West Pacific region ( Hayward 1988).

Figures

Fig. 9. Adeonella lichenoides (Lamarck, 1816). A. Field photograph of colony found among fishing debris at Kampung Kuala Temoyong, Langkawi. B–G. MSL BRY016, fragment of colony shown in A. B. Bifurcating branch. C. Group of zooids. D. Vicarious avicularium. E. Young zooids near growing edge before development of the spiramen. F. Zooids with adventitious avicularia and variably developed calcified bridges isolating the spiramen. G. Older zooids with fully developed spiramens and variously orientated adventitious avicularia. Scale bars: B = 1 mm; C = 500 μm; D–G = 100 μm.