. Bulletin of the Natural Histort Museum. Geology series. BRYOZOANS FROM CHATHAM ISLAND 17. Figs 36-37 Caleschara sp., IGNS BZ 207. 36, autozooids with variably-shaped opesiae, x 33. 37, opesiae and cryptocysts, x 60. almost certainly an artifact, especially since oral spines are not known in any other species of Calescharidae. The Red Bluff Tuff specimen most closely resembles the morphology expressed in some populations of Recent C. minuta Maplestone which lack a median process of the cryptocyst. Lack of this process is more typical of the calescharid genus Tretosiiia Canu & Bassler, 192
. Bulletin of the Natural Histort Museum. Geology series. BRYOZOANS FROM CHATHAM ISLAND 17. Figs 36-37 Caleschara sp., IGNS BZ 207. 36, autozooids with variably-shaped opesiae, x 33. 37, opesiae and cryptocysts, x 60. almost certainly an artifact, especially since oral spines are not known in any other species of Calescharidae. The Red Bluff Tuff specimen most closely resembles the morphology expressed in some populations of Recent C. minuta Maplestone which lack a median process of the cryptocyst. Lack of this process is more typical of the calescharid genus Tretosiiia Canu & Bassler, 1927 which typically has longitudinally elongate-oval opesiae, unlike those in Caleschara and the present specimen. Family MICROPORIDAE Gray, 1848 Genus MICROPORA Gray, 1848 Type species. Flustm cohacea Johnston, 1847, non Esper, 1796, by monotypy; Recent, NE Atlantic. Micropora quadriporosa sp. nov. Figs 38, 39 HOLOTYPE. IGNS BZ 186, from Pukekio, Chatham Island. No paratypes. Name. Alluding to the number of opesiular pores (four) in the zooidal cryptocyst. Description. Colony encrusting, tiny, apparently with very short pluriserial groupings of zooids. Zooids oval to subpyriform, mostly contiguous, but some very slightly disjunct and thus separated by distinct interzooidal furrows; length = mm, width = mm. Zooids generally with smooth, steeply sloping gymnocystal sides and sometimes a short proximal gymnocyst, accentuating the appearance of a raised cryptocystal rim. Cryptocyst at a lower level than the rim, more or less flat and granular, with 4 circular opesiules; one on each side proximal to the orifice, the other pair near the proximal end of the cryptocyst. Orifice more or less semicircular, but nearly twice as wide as long. No oral spines. Avicularia interzooidal, the combined rostral-opesial area somewhat pyriform in shape, indented in the middle on each side, possibly lacking a complete cross-bar. Ovicell present (broken in the only specimen), hypers
Size: 2349px × 1064px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bhlconsortium, bookc, bookcentury1900, bookcollectionbiodiversity
