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I. Plate, Mid-Aeronian chitinozoans (upper quasibaensis Biozone) from the Qusaiba-1

T. Pterochitina, 80 ft; IGR 72256 (Q43) Detail of a catenary structure showing the modification of the general shape of the vesicle after compression. Note the peculiar operculum with radial "ribs" around the central circular scar corresponding to the inter-vesicle connection, 1963.

P. Angochitina and A. , These represent possibly a new long and slender-necked transitional form between typical A. qusaibaensis and A. hemeri. 245.80 ft The prosome of these specimens is extended by an extruded thin-walled tubular structure at least as long as the vesicle itself. (6b, 9): close-up of the lips surrounding this structure, pp.72256-72256, 1995.

I. Plate, Mid-Aeronian chitinozoans (hemeri Biozone) from the Qusaiba-1 core hole

C. Caputoi and D. Costa, 70 ft; IGR 722782 (P38/2); (1a): note the short carina with rounded borders, 1971.

C. Taugourdeau and . De-jekhowsky, (2a): 167.70 ft; IGR 722782 (N40), note the three connected vesicles, the widened chamber of the species, and the mucron, pp.167-70, 1960.

P. Angochitina and A. , (5b): note the well-developed spines on the chamber, 176.05 ft. (5a): IGR 72279, p.72279, 1995.

V. Plate, Aeronian chitinozoans (hemeri Biozone) from the Qusaiba-1 core hole. Scale bar represents 100 micrometers, except for 2?3, pp.8-13

P. Angochitina and A. , 10 ft; IGR 72291 (N42) Very elongate specimen with eroded ornamentation (spines preserved only in a, 1995.

N. Anthochitina, 145.90 ft. (3): IGR 72288, close up showing the serrate membranous rim located along the margin, p.72288, 1994.

. Plectochitina, . Wood, and . Miller, (5): 145.90 ft.; IGR 72288 (S45): long processes possibly connected at their distal end. (9): core sample from 150, pp.80-72286, 1991.

C. Taugourdeau and . De-jekhowsky, 90 ft; IGR 72288 (N44) Note the presence of a mucron, and the inverted orientation of these stuck vesicles, 1960.

V. Plate, Aeronian chitinozoans (hemeri Biozone) from the Qusaiba-1 core hole. Scale bar represents 100 micrometers

V. Plate, Aeronian and early Telychian chitinozoans (hemeri and macclurei biozones) from

P. Angochitina and A. , ) core 7, sample from 40.1 ft; IGR 72351 (N44/3) The specimen is shorter than typical A. macclurei but the short spines are present on the chamber and on the neck. (3a): core 28, sample from 240, 3b): note the short spines on the chamber and on the neck, 1995.

. Plectochitina and . Taugourdeau, Core 7, sample from 40, 1963.

V. Plate, Aeronian and early Telychian chitinozoans (hemeri and macclurei biozones) from

. Ancyrochitina-camilleae-sp and . Nov, Core 19, sample from 163.0 ft. Note the short vesicle and the long and slender processes branching several times distally, p.72364

C. Cramer, Core 19, sample from 163.0 ft, 1967.

P. Belonechitina and A. , Core 19, sample from 163.0 ft, N44), specimen shorter than the type material, pp.72364-72364, 1995.

I. Plate, Early Telychian chitinozoans (macclurei Biozone) from the Baq'a-3 core hole. Scale bar represents 100 micrometers

. Fungochitina-merrelli-sp and . Nov, Core 49, sample from 450.1 ft. (1): holotype, IGR 72340 (R45), densely distributed spiny ornamentation extending on the neck); " lambda-based " spines on the chamber and on the neck

P. Angochitina and A. , Core 49, sample from 450, 1995.

. Plectochitina-alisawyiahensis-sp and . Nov, Core 49, sample from 450.1 ft. (4): IGR 72340 (P43), specimen with few processes connected at their distal end with a rim, specimen in lateral view showing the racket-like arrangement of the sets of processes

T. Pterochitina, Core 49, sample from 450.1 ft; IGR 72340 (O43/4), 1963.

. Plectochitina-alisawyiahensis-sp and . Nov, Core 49, sample from 450.1 ft; IGR 72340 (R41)

X. Plate, Early Telychian chitinozoans (macclurei Biozone) from the Baq'a-3 core hole. Scale bar represents 100 micrometers, except for 2b, pp.3-4

P. Angochitina and A. , Core 47, sample from 431.7 ft; IGR 72339 (Q45/3), cluster of compressed individuals with a fairly short neck, 1995.

. Ancyrochitina-alhajrii-sp and . Nov, Core 47, sample from 431.7 ft. (2a): paratype, IGR 72339 (O40) with minute spines on the wall (2b) (4a): holotype, IGR 72339 (O45), note the long processes, and the minute spines (length is less than 10 micrometers and their diameter less than 1 micrometer)

P. Angochitina and A. , Core 47, sample from 431, p.3, 1995.

. Fungochitina-merrelli-sp and . Nov, Core 49, sample from 450.1 ft. (5a): paratype, IGR 72340 (Q45/4); note the slender spines on the chamber; (5b): spines with lambda proximal ends and exceeding 10 micrometers length

X. Plate, Early Telychian chitinozoans (macclurei Biozone) from the Baq'a-3 core hole. Scale bar represents 100 micrometers, except for 1b and 2b

P. Angochitina and A. , (1a) Core 42, sample from 388, 1b): detail of the short conical spines, 1995.

. Armoricochitina-crassicarinata-sp and . Nov, Core 40, sample from 370.4 ft. (2a): IGR 72332 (N44/4 . (2b): detail of the slightly wrinkled surface and of the thick, but short

. Plectochitina-alisawyiahensis-sp and . Nov, Core 42, sample from 388.0 ft

. Ancyrochitina-alhajrii-sp and . Nov, Core 47, sample from 431.7 ft; IGR 72339 (L43/4 , the apparent branching of one of the processes is an artifact (organic fragment stuck on it). 7. Transitional form between Plectochitina longicornis (Taugourdeau and de Jekhowsky, 1960) and Plectochitina paraguayensis Wood and Miller, 1991.

X. Plate, Early Telychian chitinozoans (macclurei Biozone) from the Baq'a-3 core hole

A. Aculeata and T. De-jekhowsky, Core 38, sample from 350.1 ft; IGR 72329 (O48/1 , granules on the chamber (scars of spines?), 1960.

. Armoricochitina-crassicarinata-sp and . Nov, Core 40, sample from 370): holotype, IGR 72332 (S48/1 , finely wrinkled chamber surface (micro-corrugations) and thickened rim below the margin, p.72332

P. Angochitina and A. , (4): core 40, sample from 370.4 ft, typical specimens with a spherical chamber and a neck length close to / or exceeding 3 times the chamber length, IGR 72332 (P49 . (5a): core 40, sample from 370.4 ft, IGR 72332 (O44 ; (5b): typical spines on the chamber, 1995.

. Plectochitina-alisawyiahensis-sp and . Nov, Core 40, sample from 370.4 ft; IGR 72332 (P44/3 . Holotype, note the " eye " (ring-structure) at mid-length of some processes, and the distal linkage of the processes with a rim

C. Densa, Core 40, sample from 370.4 ft; IGR 72332 (R46 . (8a): these specimens arranged in chain-like structure show folding of the outer layer of their operculum (8b) in relation with the flattening of the vesicles. This form seems to announce the first appearance of the genus Margachitina (i, 1962.

X. Plate, Early Telychian chitinozoans (macclurei and obtusa biozones) from the Baq

P. Angochitina and A. , Core 38, sample from 350.1 ft; IGR 72329 (N46); typical specimen (spherical chamber and a neck length close to 3 times the chamber length), 1995.

. Armoricochitina-?-sp, Core 38, sample from 350.1 ft; IGR 72329 (P46/1 . These connected very short vesicles are possibly teratologic individuals of A. gengi sp. nov. or the very first representative of the genus Cingulochitina

. Tanuchitina, . Taugourdeau, and . De-jekhowsky, Core 38, sample from 350.1 ft. (4a): IGR 72329 (R47 ; (4b): detail of the carina, p.72329, 1960.

A. Aculeata and T. De-jekhowsky, Core 38, sample from 350.1 ft, IGR 72329 (Q49 ; large spines on the neck and on the upper part of the chamber, 1960.

X. Plate, Early Telychian chitinozoans (macclurei and obtusa biozones) from the Baq

P. Angochitina and A. Hajri, Core 34, sample at 306.0 ft, IGR 72323 (O45/3 short specimen 2. Ancyrochitina aculeata Taugourdeau and de Jekhowsky, pp.72323-72368, 1960.

C. Caputoi-da and . Costa, Core 34, sample at 306.0 ft; IGR 72323 (N45/1 specimen referred to the caputoi complex is one of the ultimate Cyathochitina recorded in the Qusaiba Member, 1971.

. Plectochitina-jacquelineae-sp and . Nov, Core 34, sample at 306.0 ft. (4a): paratype, IGR 72323 (R43 (4b): close up showing the crown of blunt short spines (ca. 10 micrometers) extending from a very short carina. (6a): holotype, IGR 72323 (P43 specimen with spines directly erected on the margin, 6b): close up of the spines

. Armoricochitina-crassicarinata-sp and . Nov, Core 38, sample from 350.1 ft

X. Plate, Early Telychian chitinozoans (obtusa Biozone) from the Baq'a-3 core hole. Scale bar represents 100 micrometers

. Armoricochitina-gengi-sp and . Nov, Core 27, sample from 250.5 ft. Holotype, IGR 72316, well-developed membranous carina (up to 20 micrometers) and the microcorrugations on the chamber

. Spinachitina-sp, Core 27, sample from 250.5 ft; IGR 72316 (R41/2), long subcylindrical chitinozoan carrying a crown of very short spines on its margin

. Plectochitina-lucasi-sp and . Nov, Core 30, sample from 271.8 ft. (3): paratype, IGR 72319 (T43/1). (7a): holotype, IGR 72319

. Plectochitina-alisawyiahensis-sp and . Nov, Core 30, sample from 271.8 ft. Various patterns of connection of the processes. (4): paratype, IGR 72319 (Q45/3) (5): paratype, IGR 72319 (R45)), detail of connections in a " buckle-like " set of processes

. Plectochitina-alisawyiahensis-sp and . Nov, Core 28, sample from 250.5 ft; paratype, IGR 72316 (R41/1), apertural view showing three sets of processes; in each set, the processes are connected through their tips

X. Plate, Early Telychian chitinozoans (obtusa Biozone) from the Baq'a-3 core hole

A. Taugourdeau and . De-jekhowsky, Core 27, sample from 250.5 ft. (1): IGR 72316 (O45), short form with serrate lips ending a short flaring neck, pp.72316-72316, 1960.

T. Conochitina, Core 27, sample from 250.5 ft; IGR 72316 (P42) Note the rim corresponding to the thickened margin, 1963.

. Plectochitina, . Wood, and . Miller, Core 27, sample from 250.5 ft; IGR 72316 (Q45) This morphotype with broad processes and a rather short neck (length of the chamber close to the length of the neck) is regarded here as typical for this species, 1991.

. Tanuchitina, . Taugourdeau, and . De-jekhowsky, Core 27, sample from 250.5 ft, p.72316, 1960.

. Plectochitina, . Taugourdeau, and . De-jekhowsky, Core 27, sample from 250.5 ft; IGR 72316 (O42) This species with very long and slender processes (up to two times the vesicle length) and a well-developed cylindrical neck has been identified previously as Plectochitina paraguayensis form, 1960.

T. Pterochitina, Core 21, sample from 192.5 ft; IGR 72310 (O42/3) Chain of three buckled and flattened vesicles, 1963.

X. Plate, Early Telychian chitinozoans from the Baq'a-3 core hole. Scale bar represents 100 micrometers, except for 1b, pp.2-6

. Fungochitina-?-sp, Core 18, sample from 170.9 ft. A crown of robust cones occurs on the margin; smaller cones are randomly dispersed on the fungiform chamber and on the neck of these specimens. (3): IGR 72307 (O41), three dimensional fungiform chamber, pp.72316-72316

. Plectochitina-sp, Core 21, sample from 192.5 ft; IGR 72310

X. Plate, Early Telychian chitinozoans (silurica Biozone) from the Baq'a-3 core hole

. Euconochitina and . Taugourdeau, Core 14, sample from 130.0 ft. (3): IGR 72302 (Q49/3), small vesicle with slightly serrate lips partly compressed vesicle with an " extruded " bottom showing an apical mark, N.B, issue.4, p.72302, 1963.

. Armoricochitina-gengi-sp and . Nov, Core 16, sample from 150.4 ft; IGR 72304 (O45), membranous carina folded and stuck above the margin

. Tanuchitina, . Taugourdeau, and . De-jekhowsky, Core 16, sample from 150.4 ft; IGR 72304 (Q43), slender and gently tapering conical vesicle, 1960.

A. Aculeata and T. De-jekhowsky, Core 16, sample from 150.4 ft, 1960.

. Plectochitina-alisawyiahensis-sp and . Nov, Paris Plectochitina alnaimi sp. nov. Paris * Plectochitina carminae Cramer, 1964.

*. Plectochitina and . Cramer, Plectochitina concinna Achab, 1978 *Plectochitina fenesdiculae Al-Ameri, 1967.

*. Plectochitina-lubniaal-ameri, Plectochitina lucasi sp. nov, 1960.

*. Plectochitina-sylvanica, Plectochitina cf. alisawyiahensis sp. nov. Paris Plectochitina cf. clathrospinosa (Eisenack, 1968) Plectochitina cf. lucasi sp. nov, 1963.

*. Sphaerochitina and . Paris, Sphaerochitina sp. indet. Paris, 1991 *Spinachitina bulmani Jansonius, 1931.