Buchneria teres (Ortmann, 1890) Ortmann, 1890

Hirose, Masato, 2012, Revision of the genus Buchneria (Bryozoa, Cheilostomata) from Japan, ZooKeys 241, pp. 1-19 : 6-8

Buchneria teres (Ortmann, 1890) comb. n. Figures 4, 5, 6

Escharoides teres Ortmann, 1890, 43, pl. 3, fig. 21; type locality, Sagami Bay.

Palmicellaria ortmanni Buchner, 1924, 210, fig. V; mentioned only in a caption to a text figure and presumably a nomen nudum; see Harmer (1957: 876).

Palmicellaria dofleini Buchner, 1924, 210, figs. F, V, pl. 17, figs. 9−12.

Buchneria dofleini : Harmer 1957, 876, pl. 17, figs. 9−12; Gordon 1989, 258, figs. 17−20.

Material examined.

Lectotype. Branched colony (MZS 36-2), collected by L. Döderlein, 1882, Sagami Bay. Paralectotype. Branched colony (MZS 36-1, 36-3; NSMT Te-738), collected by L. Döderlein, 1882, Sagami Bay. Other material examined. Fragment of colony ZSM 20043001, collected by F. Doflein, 17 October 1904, entrance of Tokyo Bay, 600 m depth; fragment of colony ZSM 20100261 collected by F. Doflein, 1904−1905, Sagami Bay; single small living colony on pebble and several fragments of living colonies (NSMT TeS-3, TeS-2), collected by NSMT from RV Shinyo-maru, 24 October 2003, Okinose, Sagami Bay (34°58.80'N, 139°31.50'E to 34°59.20'N, 139°31.20'E), 900−950 m depth, by dredge; fragments of colonies (NSMT TeS-4), collected by NSMT from research boat Rinkai-maru, 16 March 2001, SW of Hayama, Sagami Bay (35°11.46'N, 139°28.71'E to 35°11.64'N, 139°28.14'E), 432−580 m depth, by dredge; several living and dead colonies (NSMT TeS-5 to TeS-12) on dead Conchocele bisecta (Conrad, 1849) shells, collected by NSMT from RV Tansei-maru, 24 November 2007, ENE of Hatsushima, Sagami Bay (35°03.41'N, 139°12.55'E to 35°02.73'N, 139°13.73'E), 563−756 m depth, by beam trawl; single small dead colony on pebble (NSMT Te-876), collected by Nagai, 24 April 1997, SW of Shionomisaki, Wakayama Prefecture (33°24.91'N, 135°38.69'E to 33°24.95'N, 135°38.12'E), 500 m depth, by dredge.

Measurements.

ZL, 0.595−1.334 (0.978 ± 0.160); ZW, 0.214−0.840 (0.450 ± 0.133); n=65. OrL, 0.131−0.208 (0.171 ± 0.021); OrW, 0.123−0.219 (0.187 ± 0.018); n=32. AvL, 0.078−0.198 (0.110 ± 0.017); AvW, 0.055−0.148 (0.086 ± 0.016); n=82. OvL, 0.205−0.391 (0.311 ± 0.049); OvW, 0.286−0.439 (0.365 ± 0.043); n=29. Additional measurements: large suboral avicularium (LAv) length, 0.619−0.766 (0.682 ± 0.076); LAv width, 0.398−0.453 (0.426 ± 0.027), n=3.

Description.

Colony erect, rigid, dichotomously branching, widely spreading, antler-like, terminal branches slender. Basal part of colony composed of both autozoo ids and kenozooids. Branches cylindrical, 1.39-4.76 mm wide (2.77 ± 0.85 mm; n=25), with zooids opening all around, four or five zooids across in half-view (Fig. 4A, B). Autozooids subrectangular to oval, tapering proximally, cylindrical in younger ends of branches, arranged in quincunx; zooidal borders indistinct. Frontal shield convex, entirely tessellated with minute depressions, with two to six areolar pores offset from margin (Fig. 5A, B). Orifice (Fig. 5C) deeply immersed, elongated semicircular, about as wide as long, slightly concave proximally; lyrula and condyles absent. Oral spines lacking. Secondary orifice cormidial, bounded by contributions of secondary calcification from distal and lateral zooids, with suture lines often evident between the sectors; secondary orifice roughly oval in young zooids, complex in mature zooids, with suboral avicularium offset to one side and a sharp, raised flattened peristomial flange on the other, often with a sinus between the two (Fig. 5D, E). Suboral avicularium lies on peristome periphery; small, circular, with complete pivot; semicircular mandible directed proximolaterally (Fig. 5D, H); orificial side of rostrum with a rounded-triangular tooth or flange (Fig. 5E). Zooids commonly have the small suboral avicularium replaced by a larger (Fig. 6A) or much larger, hypertrophied oval (Fig. 6B) avicularium (Fig. 6A, B), with the latter type sometimes displaced proximally toward the center of the frontal shield (Figs 4C, 6C). Another type of large avicularium occurs rarely at branch bifurcations (Fig. 5F), appearing almost as a crack in the bifurcation; twice as wide as long, 0.181 mm long by 0.373 mm wide (n=1). Interzooidal kenozooids lacking orifice are interspersed with autozooids on branches (Fig. 5A), but are often much more numerous on side of branch facing inward toward the colony axis than on outer side; kenozooids encircle the base of colony (Fig. 4D). Ovicell (Fig. 5B, G, H) globose, recumbent on distal zooid, roughly as wide as long when fully formed; ooecium smooth, proximal margin slightly curved, ectooecium is not completely covering the endooecium, leaving a large central membranous foramina and small proximal membranous window (Fig. 3A, B). Ectooecium is partially covered by tessellated secondary calcification from neighboring zooids with age (Fig. 5H). The proximal margin with the central pseudopore remains uncovered in the old parts of the colony (Fig. 3C).

Distribution.

Sagami Bay, Sagami Sea, Tokyo Bay, and off Kii Peninsula, at depths of 432-950 m. The collecting depth of the specimen (1921.11.7.9.) in NHMUK is 250-330 fathoms, which means 457-603 m; therefore, the depth given in Harmer (1957) is wrong and should be in feet.

Remarks.

Ortmann (1890) first described Buchneria teres (as Escharoides teres ) based on Döderlein’s specimens from eastern Sagami Bay; these specimens had not been reexamined until this study. Buchner (1924) subsequently described Buchneria dofleini (as Palmicellaria dofleini ) from Doflein’s Sagami Bay specimens. Although Buchner’s type specimen of Buchneria dofleini was lost during WWII, I found other specimens he identified as this species in the Doflein collection at ZSM. In comparing these specimens with Ortmann’s syntypes of Escharoides teres , I found no diagnostic differences between the two; Buchner’s specimens are simply the distal younger part of branches of Escharoides teres . I thus consider Buchneria dofleini as a junior synonym of Escharoides teres , which accordingly becomes the type species of Buchneria . Buchner (1924) reported large frontal avicularia in his species, but these are enlarged suboral avicularia. Although syntypes of Buchneria teres in the Döderlein collection lack the colony base, I found an entirely kenozooidal colony base in complete colonies recently collected from Sagami Bay (Fig. 4D).