Microporella bifoliata Ulrich & Bassler, 1904: 417 Microporella bifoliata Canu & Bassler 1923: 121 Erect bifoliate species of Microporella (Bryozoa, Cheilostomata), fossil and modern Martino, Emanuela Di Taylor, Paul D. Gordon, Dennis P. European Journal of Taxonomy 2020 2020-07-02 678 1 31 8689L Ulrich & Bassler, 1904 Ulrich & Bassler 1904 [521,1066,957,984] Gymnolaemata Microporellidae Microporella Animalia Cheilostomatida 2 3 Bryozoa species bifoliata   Fig. 1; Table 1     Microporella?   bifoliata Ulrich & Bassler, 1904: 417, pl. 103, figs 6–8.    Microporella?  bifoliata–  Canu & Bassler 1923: 121, pl. 20, figs 7–11.    Material examined   Lectotype(designated here)   USA• Syntypeof  Microporella bifoliata Ulrich & Bassler, 1904; Maryland, Cordova; Miocene; Choptank Formation; USNM 68592A( Fig. 1A–B).   Paralectotype(designated here)   USA• Syntypeof  Microporella bifoliata Ulrich & Bassler, 1904; Maryland, Cordova; Miocene; Choptank Formation; USNM 68592B( Fig. 1C–D).  Other material   USA• 4 specimens, syntypesof  Microporella bifoliata Ulrich & Bassler, 1904; Maryland, Cordova; Miocene; Choptank Formation; USNM 68592Cto 68592F.    Description COLONY. Erect with bifoliate fronds up to several cm wide, curved; colony base and interzooidal communication not observed. AUTOZOOIDS. Distinct, separated by narrow grooVes, rectangular, longer than wide (mean L/W = 1.76). Frontal shield flat; marginal areolae typically numbering about 16 (12–18), Variable in size ( 15–40 µm), funnel-shaped, sometimes subdivided internally; reduced number of non-marginal pseudopores, placed more centrally on the frontal shield, irregularly spaced. PRIMARY ORIfICE. Terminal, semielliptical, widest medially, hingeline slightly concave, without teeth or condyles; oral spines lacking; no peristome. ASCOPORE fIELD. A narrow, raised area of gymnocystal calcification beneath leVel of adjacent frontal shield but at approximately same leVel as orifice, located Very close to its hingeline; elliptical, ca 35 × 50 µm, distal margin with projecting, semielliptical tongue leaVing a crescent-shaped opening, ca 10 × 30 µm, with radial spines. AVICULARIUM. Single, located at the same level of ascopore, oriented laterally; crossbar complete; opesia semielliptical; rostrum subtriangular, the distal end a little rounded, not channelled.   Fig. 1.  Microporella bifoliata Ulrich & Bassler, 1904, Miocene, Choptank Formation, Maryland, USA. A–B. Lectotype USNM 68592A. A. General view of the branch fragment. B. Group of zooids, mostly ovicellate. C–D. Paralectotype USNM 68592B. C. Group of autozooids. D. Close-up of an autozooid. Scale bars: A = 1 mm; B–C = 200 µm; D = 100 µm.   Table 1.Measurements in µm of  Microporella bifoliata Ulrich & Bassler, 1904, Miocene, Choptank Formation, Maryland, USA; lectotype USNM 68592A, paralectotype USNM 68592B.     N (zooids, colonies)  Mean  SD  Min  Max   ZL 16, 2 509 ±73 385 662   ZW 16, 2 290 ±27 245 330   OL 10, 2 91 ±4 85 98   OW 10, 2 114 ±9 102 126   AvL 16, 2 104 ±12 78 122   AvW 16, 2 86 ±14 62 116   OvL 8, 1 243 ±12 231 261   OvW 8, 1 273 ±27 238 312 OVICELL. Prominent, circular in outline, not personate and not obscuring orifice; calcification similar to frontal shield; pseudopores variable in number, scattered over entire surface, variably spaced.    Remarks This extinct species was described from the Miocene (Choptank Formation 12.6–14.4 Ma; Andrews 1988) of Maryland( Fig. 1). The form of the mandible is not known in this fossil species, but the fact that the avicularia have closed distal ends without channels may suggest that mandibles were not setose and had a shape identical to that of the rostrum. 2804045303 USNM United States of America Syntype Miocene Cordova 2 3 USNM 68592A 1 Maryland syntype 2804045319 USNM United States of America Syntype Miocene Cordova 2 3 USNM 68592B 1 Maryland syntype 2804045314 USNM United States of America Cordova Choptank Formation Miocene 2 3 USNM 68592C, 68592F 4 Maryland syntype