Guelb el Ahmar, GEA 2 (Jurassic of Morocco)

Where: Figuig, Morocco (32.5° N, 3.1° W: paleocoordinates 26.9° N, 0.9° E)

• coordinate stated in text

When: Lower Anoual Member (Anoual Formation), Bathonian (168.3 - 166.1 Ma)

• The Guelb el Ahmar fauna is stratigraphically located in the upper part of the Anoual Formation... subdivided into a thick continental lower member, and a shallow marine carbonaceous upper member. The lithology and sedimentary structures of the lower member suggest a flooding plain and/or deltaic depositional environment. This is consistent with the large fossil trunks that are common in that unit. The fossiliferous levels yielding the Guelb el Ahmar (GEA) vertebrate fauna belong to the upper part of the lower member of the Anoual Fm. Sites GEA 3 and GEA 1 correspond to the same level of calcareous lacustrine limestones, which underlies site GEA 2.

Environment/lithology: fluvial-deltaic; lithified, gypsiferous, brown marl

• "The lithology and sedimentary structures of the lower member suggest a flooding plain and/or deltaic depositional environment."
• Two contiguous fossiliferous beds yielding microvertebrates have been sampled at Guelb el Ahmar. The lower fossiliferous level is a lacustrine limestone yielding small and medium-sized fossil remains, including fishes and turtles. The top of this lacustrine bed is capped by a duricrust yielding abundant remains of fishes such as Lepidotes; it was sampled especially at GEA 1 and GEA 3 sites. This crust of a few centimeters (its thickness varies laterally) is overlaid by a thin bed of dark-brown, slightly lignitic marls that were intensively sampled (GEA 2) for screen-washing. They are covered by 2–3mof green-grayish marls which pass upward into reddish mudstone and cross-bedding sandstone with bioturbation.

Size classes: macrofossils, mesofossils, microfossils

Preservation: coalified

Collection methods: bulk, surface (in situ), mechanical, peroxide, sieve,

Primary reference: H. Haddoumi, R. Allain, S. Meslouh, G. Metais, M. Monbaron, D. Pons, J.-C. Rage, R. Vullo, S. Zouhri and E. Gheerbrant. 2016. Guelb el Ahmar (Bathonian, Anoual Syncline, eastern Morocco): first continental flora and fauna including mammals from the Middle Jurassic of Africa. Gondwana Research 29:290-319 [P. Barrett/T. Cleary]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 176120: authorized by Paul Barrett, entered by Terri Cleary on 29.01.2016, edited by Philip Mannion

Creative Commons license: CC BY (attribution)

Taxonomic list

unclassified
  -
Ostracoda
  -
Ostracoda indet. Latreille 1802 ostracod
Gastropoda
 Basommatophora - Planorbidae
Planorbidae indet. Rafinesque 1815 pulmonate
 Basommatophora - Lymnaeidae
Lymnaeidae indet. Rafinesque 1815 pulmonate
 Valvatoidea - Valvatidae
Valvatidae indet. Gray 1840 snail
Actinopteri
 Teleostei -
Osteoglossiformes indet. Berg 1940
"small squamules, rectangular or polygonal in shape, with ornamentation consisting of small granules bent in the same direction"
 Neopterygii -
Lepisosteiformes indet. Hay 1929 gar
"Lepidotes sp. or Scheenstia sp.", isolated teeth
 Halecomorphi -
cf. Ionoscopiformes indet. Grande and Bemis 1998
"small ganoid scales"
Osteichthyes
 Dipnoi - Arganodontidae
Arganodus sp. Martin 1979 lungfish
isolated teeth
Coelacanthimorpha
 Coelacanthiformes - Mawsoniidae
Mawsoniidae indet. Schultze 1993 coelacanth
skull bones
Osteichthyes
 Temnospondyli -
? Lissamphibia indet. tetrapod
GEA 2-2, incomplete maxilla, "tentatively assigned to lissamphibians on basis of the morphology of its teeth"
 Temnospondyli - Albanerpetontidae
Albanerpetontidae indet. Fox and Naylor 1982 tetrapod
GEA 2-22, incomplete maxilla; GEA 2-21, incomplete frontal
 Caudata -
? Caudata indet. salamander
GEA 2-29, fragment of dentary
Reptilia
 Testudinata -
Testudinata "sp. 1" Oppel 1811 turtle
morphotype 1 represented by "about 50 plate fragments" from sites GEA 2 and 3
Testudinata "sp. 2" Oppel 1811 turtle
morph. 2 is represented "at least by a neural plate" from sites GEA 2 and 3
Testudinata "sp. 3" Oppel 1811 turtle
morph. 3 is represented "by smooth plates" from sites GEA 2 and 3
Testudinata "sp. 4" Oppel 1811 turtle
morph. 4 is represented "by two small incomplete costal plates" from sites GEA 2 and 3
 Diapsida -
Diapsida indet. Osborn 1903 diapsid
GEA 2-40 to 2-45, six vertebral centra
 Theropoda -
Theropoda indet. theropod
a few nearly complete teeth
 Ornithischia -
Ornithischia indet. ornithischian
single, poorly preserved tooth
cf. Stegosauria indet. ornithischian
one poorly preserved tooth
 Pterosauria -
Pterosauria indet. pterosaur
teeth (morphotype 2)
 Pterosauria - Rhamphorhynchidae
Rhamphorhynchidae indet. Seeley 1870 pterosaur
teeth (morphotype 1)
 Loricata -
Theriosuchus sp. Owen 1878 crocodilian
numerous small teeth
 Loricata - Teleosauridae
Teleosauridae indet. Geoffroy 1831 marine crocodile
numerous small slender teeth
 Squamata -
Squamata indet. Oppel 1811 lizard
indeterminate non-ophidian squamate; GEA 2-24, incomplete maxilla; GEA 2-25, incomplete dorsal vertebra; GEA 2-27, proximal part of femur
Scincomorpha indet. Camp 1923 lizard
GEA 2-26, fragment of bone, bearing teeth
? Scincomorpha indet. Camp 1923 lizard
GEA 2-28, fragment of bone bearing one complete tooth
cf. Parviraptor sp. Evans 1994 lizard
GEA 2-30, -34, -35, -36, four vertebral centra
 Lepidosauria -
Rhynchocephalia indet. Günther 1867 rhynchocephalian
GEA 2-20, one fragment of dentary with two incomplete teeth; GEA 2-18, fragment of maxilla bearing two teeth bases
 Choristodera -
cf. Choristodera indet. choristodere
GEA 2-31, fragmentary dentary; GEA 2-23 and 2-37, two centra of dorsal vertebrae; GEA 2-28, centrum of one anterior caudal vert.; GEA 2-39 (tentative assignment), centrum of dorsal vert.
Mammalia
 Dryolestoidea -
cf. Dryolestida indet. Prothero 1981 mammal
GEA 2-33, fragment of tooth
 Prototribosphenida - Amphitheriidae
Amphitheriidae indet. Owen 1846 mammal
GEA 2-1, fragment of juvenile right dentary; GEA 2-32, fragment of edentulous right dentary
Schizosporis
  -
Schizosporis sp. Cookson and Dettmann 1959
Chlorophyceae
  -
Botryococcus sp. Kutzing 1849
unclassified
  -
Charophyta indet. Migula 1890
Pinopsida
 Pinales - Araucariaceae
 Pinales - Cheirolepidiaceae
Classopollis sp. Pflug 1953
 Pinales -
Cycadopites
  -
Cycadopites sp. Wodehouse 1933
Pteridopsida
  -
Cyathidites sp. Couper 1953
Lycopsida
  -
Leptolepidites sp. Couper 1953
 Gymnospermophyta -
Alisporites sp. Daugherty 1941
Pinidae
 Cupressales - Pinidae