148 
Table 22 Quantitative comparision of Leioclema indentata with other Carboniferous Leioclema species (dimensions in mm). 
P.N. WYSE JACKSON 
ZD AD IWT Z2 ET TE 
L. indentata sp. nov. 1.15-2.18 0.12-0.20 0.06—0.26 4-8 0.68-1.10 0.28-0.51 
L. porosum Crockford, 1947 20 0.2—0.25 0.08 - - - 
L. shumaradi Girty, 1908 3F5 0.15-0.20 0.20 - - = 
L. punctatum (Hall, 1858) 2.00—5.00 0.15—0.20 = 5-6 = = 
L. pushmatahensis Harlton, 1933 0.73=1.02 - - - - 
L. avonense Lee, 1912 22.00 ~ - 6 - = 
°L. hirsutum Moore, 1929 1.00-1.40 0.16—0.20 0.1 - 0.9 0.40-0.45 
L. tubulosa Nekhoroshey, 1956 3.00-5.00 0.13-0.17 - 5.5-6.5 - = 
L. bifoliata Nikiforova, 1927 4.0 0.20-0.25 0.1 = 12 0.8 
?L. kobayashii Sakagami, 1962 2.60-3.60 0.21-0.29 0.32-0.40 = ~ - 
?L. uzuraense Sakagami, 1964 = 0.16—0.22 - 10 - - 
L. cassis Trizna,-1958 1.80 0.18—0.20 - 10 - = 
L. echinata Trizna, 1958 1.60 0.16—0.18 - 7-10 = = 
L. podunskense Trizna, 1958 2.20-3.20 0,15-0.18 = 5-7 - - 
L. rojkiensis Trizna, 1958 2.00 0.20-0.22 - 6-7 - - 
L. semetra Trizna, 1958 2.75-3.00 0.14-0.16 = 11-12 - - 
L. textila Trizna, 1958 0.80-0.90 0.10-0.16 - 6 = - 
L. clara Trizna, 1962 3.30 0.16—0.20 - 8-9 ~ - 
L. gracillimum Ulrich, 1888b 1.00-1.50 0.10-0.15 - 8-9 - — 
L.araneum Ulrich, 1890 Adnate 1.00 0.2 - 9-10 - - 
L.foliatum Ulrich, 1890 Adnate 1.00—1.50 0.2 - 6 - - 
L. subglobosum Ulrich, 1890 - 0.15—0.20 ~ 8-9 - - 
L. washsmuthi Ulrich, 1890 Adnate <1.00 0.2 - 6 - - 
Data from original sources. 
elevated above the autozooecial apertures. Monticules are not devel- Dyscritella miliaria (Nicholson, 1881) Figs 63-66 ) 
OSes v1881  Monticulipora tumida var. miliaria Nicholson: 123, pl.3, 
DISCUSSION. Leioclema indentata is very rare in the Viséan of fig.2. ; ¥ . a ‘ | 
County Fermanagh. Only ten zoarial fragments were found; all of 1884c Monticulipora tumida var. miliaria Nicholson; Vine: 101. | 
these are silicified and consequently internal structures are not well 1912 Dyscritella miliaria (Nicholson); Lee: 178, pl.16, figs 7 
known. However, some fine skeletal features such as autozooecial 1950 Dyscritella miliaria (Nicholson); Termier & Termier, p.15, 
diaphragms are preserved, and are seen in broken fragments. pl.5s, figs 4-6, 9, pl.60, fig.7, pl.65, figs 7-9. } 
L. indentata can easily be recognised by the indentation of the 1987 Dyscritella miliaria (Nicholson), Bancroft: 196. [ 
autozooecial apertures by six to seven large acanthostyles, and from LECTOTYPE. Herein designated AUGD 10135a, Carboniferous 
surface ornamentation. Coefficients of variation for measured pa- 
rameters are all low, including that for interapertural wall thickness 
(IWT). 
25 other Leioclema species have been described from the Carbon- 
iferous (McKinney 1973, Astrova 1978, and herein), of which only 
L. avonense Lee, 1912, from the Avon area, and Leioclema sp. from 
North Wales (Bancroft, Somerville & Strank, 1988), occur in the 
British Isles. All are compared with L. indentata in Table 22 above. 
L. avonense is unusual in that the zoarium is very thick, exozone 
walls are not thickened, and that mesozooecia are few. Thus, its 
taxonomic position 1s debateable, and may only be resolved by 
examining Lee’s original material. 
L. indentata has a gross morphology similar to the North Ameri- 
can speciesL. gracillimum Ulrich, 1888b. However, apertural spacing 
and acanthostyle diameter are considerably less in the latter. 
STRATIGRAPHICALRANGE. Lower Carboniferous ( Viséan, Asbian). 
DISTRIBUTION. Counties Fermanagh and Leitrim, Ireland. 
Suborder AMPLEXOPORINA Astrova, 1965 
Family DYSCRITELLIDAE Dunaeva and Morozova, 1967 
Genus DYSCRITELLA Girty, 1911 
TYPE SPECIES. Dyscritella robusta Girty, 1911, by original desig- 
nation from the Lower Carboniferous of Arkansas, U.S.A. 
shales; Redesdale, Northumberland, England; Nicholson Collec- 
tion. 
PARALECTOTYPES. Herein designated AUGD 10135b (2 speci- 
mens in cavity slide); Carboniferous shales; Redesdale,, 
Northumberland, England; Nicholson Collection. RSM 1967.66.384, |” 
RSM 1967.66.387; Carboniferous shales; Redesdale, Northumber-~ 
land, England; Nicholson Collection. 1 
MATERIAL. BELUM K3442, K3608 Upper part of the Glenc 
Limestone (Viséan, Asbian), Sillees River, County Fermanagh. 
DIAGNOsIS. Dyscritella with robust dendroid zoarium and irregu- 
larly dichotomising branches. Autozooecia are developed throughou 
the zoarium. Zooecial walls are thin in the endozone but are thick | * 
and of constant width in the exozone. Basal diaphragms are rare an 
indistinct. Autozooecial apertures are circular and of moderate size 
Interapertural areas are of variable width, and exilazooecia ar 
abundant. Maculae are quite common. Prominent, large acanthostyle: 
occur at interzooecial intersections interspersed with smalle 
acanthostyles between. 
DESCRIPTION. The dendroid zoarium is robust, the longest frag) | 
ment examined attaining a length of 30.6mm. Bifurcation is rare bul | 
where it occurs no increase in branch width accompanies it. 
Autozooecia originate in the endozone by interzooecial budding) }, 
From the endozone they diverge at a low angle, but in the exozon| |» 
they turn through 80° to lie perpendicular to the zoarial surface. I} 
the endozone zooecial walls are thin and undulatory. Walls thicke} 
