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Paragonyaulacysta retiphragmata

Paragonyaulacysta retiphragmata Dörhöfer and Davies, 1980, p.31–32, figs.14,29D–F. Emendation: Below, 1990, p.60,62.

Holotype: Dörhöfer and Davies, 1980, figs.14, 29D-F
Locus typicus: Elf Jameson Bay, Prince Patrick Island, District of Franklin, Northwest Territories, Canada
Stratum typicum: Callovian

Original diagnosis: Dörhöfer and Davies, 1980, p. 32.
A species of Paragonyaulacysta with finely reticulate autophragm and punctate sutural crests.
Tabulation 4", 3a, 6"", 6c, 6""", 2p, 2pv, 1"""", ?s.
Archaeopyle 3I (1-3).
Remarks: The reticulum consists of very fine irregular meshes (0.25-1.0 µm). The height of the sutural crests is about 3 µm. In all other respects the species corresponds to P. calloviensis.
Length: 61(54)48 µm; breadth 45(41)35 µm.

Emended description: Below, 1990, p.60, 62
Archaeopyle anateriorly intercalary, 2a. Operculum secate, general opercular formula 2a(s). The archaeopyle is always monotabular 2a, which is also the case in the holotype. Dörhöfer and Davies 1980 incorrectly described a tritabular archaeopyle.
Vesicle-/plate-arrangement of the amphiesma cop, pop, cap, 3", 2a, 6"", 7c, 6""", 2"""", as, FM, ls, rs, ps; 1" exsert with adelopore on the 1"/6"" suture, 1a four-sided, 2a hexagonal. Growth of thecal plates ?gonyaulacoidal. Zygote cyst proximate, acavate, cornucavate, finicavate, elongate polyedrical, epicyst high, tentoriate, with stretched apical horn, hypocyst slightly shorter, mensaform, with ventrally sloping polar plane, equatorial cross-section circular. Wall consisting of thin pedium and loosely attached luxuriate reticulum, which is partially absent or distally closing into the tegillum, but which finitely melts into low, carinate, broad-based, distally smooth septa, which divides the cyst into plates, trichocyst pores often reflected as rings.
Paratabulation XPR/cop, pop, cap, 3", 2a, 6"", 7c, 6""", 2"""", as, ls, ps; cop tiny, as the oval tip of the apical horn, enclosed by the horse-shoe- shaped pop, tiny cap connected distally. 3 apicals: very small planate 1" (V) exsert with porichnion on the 1"/6"" suture, VIII 2" (LVL). IX 3" (VVR). 2 anterior intercalaries: small caroidal 1a (DL) and linteloid 2a (D). 6 precingulars: anteriorly bigeniculate VI-nE 1"" (VVR), anteriorly geniculate V-nE 2"" (LVL), V-nE 3"" (DDL), V-nE 5"" (RVR) and V-nE 6"" (VVR), anteriorly linear IV-nE 4"", suture 3""/4"" dorsal. Cingulum leavorotatory, heptapartite. 6 postcingulars: posteriorly linear VI-nE 1""" (VVL), IV-nE 2"" (VL), IV-nE 4""" (D), IV-ne 5""" (R) and VI-ne 6""" (VVR), posteriorly geniculate V-nE 3""" (DL), 2 antapicals: V 1"""" sloping towards VL, VI 2"""" towards V. Sulcus tabulated or sulcal are nonfinate againstFM: small VI as, steno V FM, small V ls, and large omegaform VI ps between 1"""" and 2"""".
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