Antropora minor ( Hincks, 1880 )

Dick, Matthew H., Tilbrook, Kevin J. & Mawatari, Shunsuke F., 2006, Diversity and taxonomy of rocky-intertidal Bryozoa on the Island of Hawaii, USA, Journal of Natural History 40 (38 - 40), pp. 2197-2257 : 2209-2210

Antropora minor ( Hincks, 1880)

( Figure 5A, B )

‘‘? Membranipora trifolium S. Wood , var. minor ’’ Hincks 1880, p 87, Plate 11, Figure 6 . Antropora minor: Tilbrook 1998, p 34 , Figure 2A–F ; 2006, p 30, Figure 4B ; Tilbrook et al.

2001, p 41, Figure 3A .

Measurements ZL, 0.35–0.48 (0.422¡0.044). ZW, 0.23–0.35 (0.273¡0.039). OpL, 0.21–0.28

(0.240¡0.023). OpW, 0.14–0.16 (0.149¡0.009).

Description

Colony unilaminar, encrusting. Gymnocyst scarcely evident; cryptocyst ( Figure 5A, B ) very wide and shallowly sloping proximally, narrowing and steep distally, with coarse, rather irregularly arranged tubercles; opesia large, irregularly oval or subtriangular. Interzooidal avicularia small, on a raised cystid; some zooids have a kenozooidal papilla at proximal end, replacing or together with an avicularium. Ovicells lacking, but the raised, smooth distal zooidal margin in fertile zooids ( Figure 5B ) may represent a vestigial ovicell. Spines lacking. Autozooid-sized vicarious avicularia can occur, but are absent in our specimen.

Remarks

Only one small, dead colony fragment was found, at Kapa’a.

Distribution

Circumtropical ( Tilbrook, 1998); not previously reported from the Hawaiian Islands.

Figures

Figure 2. Photographs of rock-pile habitats examined at study sites on the Island of Hawaii; all taken within an hour of low tide (20.03 to +0.15 m referenced to mean lower low water). (A) Kealakekua Bay; study site is shallow inlet beginning at centre and extending to just below left centre; plastic kayak at upper right indicates scale. (B) Whittington Beach Park; sheltered lagoon inside benchrock barrier, part of which can be seen in distance at far upper right; scale indicated by water bottle at lower left. (C) Kapa’a Beach Park; an exposed site with roundedboulder beaches (centre) and solid benchrock (in distance, upper right); sampling site was a tidepool in the benchrock just beyond the upper right of the photograph. (D) Kiholo Bay; entrance to large lagoon separated from the sea by a long barrier spit, on which palm and other trees are growing; end of spit is seen just above right centre, with lagoon evident beyond that in the distance; the shallow area with boulders protruding from water, left to right just below centre, was examined for bryozoans; photograph taken about an hour before low tide.

Figure 3. (A–C) Alderina flaventa n. sp., holotype (NHM 2006.7.21.1): (A) group of autozooids and ovicellate zooids; (B) ovicellate zooid; (C) colony margin showing uniporous septula. (D) Parellisina albida (Hincks): autozooids, ovicellate zooid, and interzooidal avicularia. All specimens bleached. Scale bars: 500 Mm (A, C, D); 400 Mm (B).

Figure 4. Corbulella extenuata n. sp., holotype (NHM 2006.7.21.5): (A) autozooid, unbleached; (B) marginal zooids, bleached; note cap-like reduced ovicells; (C) autozooids and interzooidal avicularium (centre), bleached; (D) lateral wall of marginal autozooid showing septula, bleached. (B–D) are from same colony as (A), after bleaching. Scale bars: 500 Mm (A, C, D); 400 Mm (B).

Figure 5. (A, B) Antropora minor (Hincks): (A) autozooids, bleached; (B) autozooids, bleached; zooid at right is a brooding zooid, with a raised, smooth distal margin that may represent a vestigial ovicell. (C) Beania discodermiae (Ortmann): autozooids, unbleached. (D) Micropora rimulata Canu and Bassler: autozooids and ovicellate zooids, bleached. Scale bars: 200 Mm (A, B); 500 Mm (C, D).

Figure 6. (A, C, E, G) Puellina harmeri Ristedt: (A) autozooid, ovicellate zooids, and avicularia; (C) ancestrula and periancestrular zooids; (E) marginal zooids, showing long distal spines and marginal avicularium; (G) oblique view of autozooids and ovicellate zooids. (B, D, F, H) Puellina septemcryptica n. sp.: (B) paratype (NHM 2006.7.21.7),