Cystodictya pustulosa, Ernst & Minwegen, 2006

Ernst, Andrej & Minwegen, Elke, 2006, Late Carboniferous bryozoans from La Hermida, Spain, Acta Palaeontologica Polonica 51 (3), pp. 569-588 : 573-575

Cystodictya pustulosa sp. nov.

Figs. 3G, H, 4A, B; Table 3.

Derivation of the name: The name derives from Latin pustulae (= vesicle) and refers to the presence of abundant vesicles.

Type material: Holotype ( SMF 1776 ) and two paratypes ( SMF 1743 and 1751).

Type locality: La Hermida, Spain .

Type horizon: Picos de Europa Formation , Moscovian, Upper Carboniferous .

Other material.—SMF 1738, 1778, 1769, and 14 additional fragments.

Diagnosis.— Cystodictya pustulosa sp. nov. differs from the most similar species C. zigzag Ulrich, 1888 in having more closely spaced apertures (12–13 versus 10 per mm longitudi− Family Goniocladiidae Nikiforova, 1938

nally in C. zigzag ). The new species differs from other Genus Cystocladia nov.

Cystodictya species in having abundant skeletal vesicles. Derivation of the name: The name derives from a combination of the

Greek words cystos (= vesicle) and clados (= branch), signifying the Description.—Bifoliate frondescent colony. Branches lens−

presence of vesicles and the branching colony shape.

shaped in cross−section, 1.30–3.74 mm wide and 1.14–2.34

Type species: Cystocladia hispanica sp. nov.

mm thick. Mesotheca 0.03–0.04 mm thick, three−layered,

Diagnosis.—The new genus is defined by ramose branched consisting of a medial dark layer and two pale outer layers.

colonies, long autozooecia budding in bundle in endozone Autozooecia short, budding parallel to the mesotheca for a

and opening on one side of branches, large lunaria, well dedistance of about three zooecial diameters, semicircular or

veloped vesicular skeleton, and lacking diaphragms, hemitrapezoid in basal cross section, not separated by vesicles at

phragms or hemisepta. Cystocladia gen. nov. differs from mesotheca; completely separated by vesicular skeleton in the

other goniocladiids in absence of a median lamina which diexozone, arranged in 5–8 rows on branches. Apertures roun−

vides the branch into two symmetrical halves

ded to oval, spaced 12–13 longitudinally and 7–8 diagonally

Discussion.—The fistuliporid genus Cheilotrypa Ulrich, 1884 per 5 mm. Lunaria distinct, shallow, occupying half of the

is similar to Cystocladia gen. nov., differing in having a radial apertural space, containing 3–4 styles. Both inferior and su−

arrangement of autozooecia on the branch. Another similar perior hemisepta present, long, curved proximally; superior

fistuliporid genus Fistulocladia Bassler, 1929 differs in havhemisepta located at transition from endozone to exozone;

ing a bundle of vesicles in the axial part of the branch.

inferior hemiseptum hook−shaped, located at the floor of the autozooecium below the superior hemiseptum. Terminal dia− Stratigraphic and geographic range.—Picos de Europa Forphragms occasionally present, planar or curved distally. Ske− mation, Moscovian, Upper Carboniferous; La Hermida, Spain. letal vesicles abundant, box−shaped, large and high at their

Cystocladia hispanica sp. nov.

bases becoming smaller and flatter in the exozone, with

Fig. 4C–E; Table 4.

rounded roofs, polygonal in tangential section, covered at the colony surface by thick layer (0.12–0.23 mm) of dense skele− Derivation of the name: After Spain.

ton, arranged in interspaces between autozooecia in 3– 4 Type material: Holotype ( SMF 1774 ) and two paratypes ( SMF 1777 and

1747).

rows.

Type locality: La Hermida, Spain .

Stratigraphic and geographic range.— Picos de Europa For− Type horizon: Picos de Europa Formation , Moscovian , Upper Carbonifmation , Moscovian , Upper Carboniferous; La Hermida, Spain. erous .

Other material.—SMF 1744, 1753, 1798, 1799, 2110. Table 5. Measurements of Stenophragmidium isospinosum Ernst, Schäfer, and Reijmer, 2005 . N, number of measurements; X, mean; SD, stan−

Diagnosis.—As for genus. dard deviation; CV, coefficient of variation; MIN, minimal value;

Description.—Ramose branched colonies. Branches rounded MAX, maximal value.

to slightly flattened, frequently ramifying dichotomously.

Autozooecia relatively long, arranged as a bundle in the N X SD CV MIN MAX endozone, opening on one side of branches, circular to oval aperture width 20 0.24 0.018 7.580 0.20 0.28

in cross section, isolated by vesicular skeleton. Apertures oval, arranged in a quincuncial pattern, spaced 4 per 2 mm

longitudinally. Lunaria large, occupying more than half of Abundant microacanthostyles protruding from walls in the the autozooecial diameter, consisting of moderately thick exozone, positioned perpendicular to the skeletal lamination,

calcitic skeleton. Vesicles relatively small, polygonal in tan− arranged irregularly, 0.01–0.02 mm in diameter. Zooecial gential section, high in the endozone but becoming flat in the walls finely laminated, 0.015 –0.020 mm thick in the endo−

exozone, in 1–2 rows separating autozooecia. Hemisepta ab− zone; displaying reversed U−shaped lamination and dark, ser−

sent, diaphragms not observed. Colony surface covered by rated median wall lining, 0.08–0.10 mm thick in the exozone.

granular calcitic material. Discussion.—The La Hermida material corresponds exactly with Stenophragmidium isospinosum Ernst, Schäfer , and Reij−

Order Trepostomida Ulrich, 1882 mer, 2005 described from the Valverdín section of the San

Suborder Amplexoporina Astrova, 1965 Emiliano Formation in the Upper Carboniferous (Westphalian B/C) of the Cantabrian Mountains.

Family Anisotrypidae Dunaeva and Morozova, 1967

Genus Stenophragmidium Bassler, 1952 Stratigraphic and geographic range.—San Emiliano Formation, Upper Carboniferous (Westphalian B/C); Valverdín,

Type species: Stenophragma lobatum Munro, 1912 , by original desig− Cantabrian Mountains , northern Spain. Picos de Europa For−

nation; Lower Carboniferous (Viséan) of England. mation, Moscovian, Upper Carboniferous; La Hermida, Spain.

Diagnosis.—Encrusting, rarely ramose colonies. Autozooecia possessing rounded−polygonal and oval apertures. Walls Order Rhabdomesida Astrova and Morozova, 1956

moniliform. Hemiphragms short, positioned on one side of

Suborder Rhabdomesina Astrova and Morozova, 1956

autozooecia. Exilazooecia rare. Acanthostyles both large and small, rarely only small or only large (translated after Astro− Family Rhabdomesidae Vine, 1885

va 1978). Genus Rhabdomeson Young and Young, 1874

Discussion.— Stenophragmidium Bassler, 1952 differs from = Coeloconus Ulrich, 1889

Tabulipora Young, 1883 by the presence of hemiphragms Type species: Rhabdomeson progracile Wyse Jackson and Bancroft ,

instead of ring septa. 1995b, by subsequent designation of Wyse Jackson and Bancroft (1995b) (ICZN Opinion 1874); Lower Carboniferous, England.

Stratigraphic and geographic range.—Lower to Upper Car− Diagnosis.—Rhabdomesid with delicate dendroid colony

boniferous; Europe, North America, China, and Russia. having irregularly dichotomising branches. Autozooecia regularly budding around central axial cylinder in annual or

Stenophragmidium isospinosum Ernst, Schäfer , and spiral pattern. Hemisepta common. Autozooecial apertures

Reijmer, 2005 elliptical, pyriform or rhombic, closely spaced, arranged in

Fig. 4F–H; Table 5. quincunx on colonial surface; of constant or variable dimen−

2005 Stenophragmidium isospinosum sp. nov.; Ernst et al. 2005: 306, sions around branch. Stylets abundant and structurally di−

pl. 2: 4–5. verse (after Wyse Jackson and Bancroft 1995a).

Material.— SMF 1730, 1731, 1745. Stratigraphic and geographic range.—Middle Devonian to

Description.—Encrusting colony of thin lamellar expansions, Upper Permian; worldwide.

0.6 mm thick. Autozooecial apertures rounded−polygonal, 6–7

spaced in 2 mm distance and 10 in 1 square mm of the colony Rhabdomeson cf. propatulissimum Ceretti, 1963

surface. Diaphragms absent in autozooecia. Hemiphragms Fig. 5A–D; Table 6.

common, positioned on proximal side of autozooecial cham−?1963 Rhabdomeson propatulissimum sp. nov.; Ceretti 1963: 315–316,

ber. Exilazooecia not observed. Macroacanthostyles absent. pl. 25: 13. Material.— SMF 1758, 1763, 1764, 1766, 1770, 1779.