Sahel Alma or Sahel Aalma is a Late Cretaceous paleontological site and Konservat-Lagerstätte in Keserwan-Jbeil, Lebanon. Located near the town of the same name, it documents well-preserved deepwater marine fossils dating to the late Santonian stage of the Cretaceous. It is often associated with the slightly older, similarly famous Sannine Formation sites (Haqel, Hadjula, and Nammoura), with these four sites being together referred to as the "Fish Beds" of Lebanon.
It is one of the few fossiliferous units of the Chekka Formation, a wider geological formation in Lebanon deposited from the Late Cretaceous to the early Paleogene. The site is no longer accessible for scientific research as buildings were constructed over it.
Description
Much like the fossil sites of the older Sannine Formation, Sahel Alma contains exquisitely preserved marine fossils from the Tethys Ocean, deposited off the northern coast of the Afro-Arabian continent. However, unlike the Sannine Formation sites, which were deposited in relatively shallow waters near the shore on the inner continental shelf, Sahel Alma was deposited in a deepwater habitat off the continental slope, at depths estimated to be greater than , likely at the transition between the sublittoral and bathyal zones in dysphotic or aphotic conditions. This has caused it to preserve a distinct fauna from the Sannine Formation, with a significant number of deepwater arthropods and chondrichthyans.
As with the sites of the Sannine Formation, the fossils of Sahel Alma are very well-preserved, and include the soft body parts of cartilaginous fish and cephalopods. Palaeoctopus, the first fossil octopus discovered with preserved soft tissues, was discovered from Sahel Alma.
History
Sahel Alma is one of the oldest-known fossil sites in Lebanon, second only to the Haqel site of the Sannine Formation. It has been known of since the Seventh Crusade in the 13th century, when bricks quarried out of it were used to build the eponymous Maronite monastery at Sahel Alma. A fossil fish presented to King Louis IX around this time may have been from the site. The site was also likely documented by C. F. Volney during the early 1780s. British adventurer Lady Hester Stanhope settled near Sahel Alma in the early 19th century, and helped to collect and circulate fossils from the site and Haqel. Paul-Émile Botta was also another prolific early researcher of the site.
The site is no longer accessible for scientific research as buildings were constructed over it, due to the purchase of the site by a private company, which restored the Sahel Alma monastery as a hotel.
Paleobiota
Vertebrates
Cartilaginous fish Chondrichthyans reported from Sahel AlmaGenusSpeciesNotesImagesAcanthoscylliumA.sahelalmaeA bamboo shark.AlmascylliumA.cheikheliasiA bamboo shark.AnomotodonA.plicatusA goblin shark.BritobatosB.primarmataA potential relative of the thornback rays.CentrophoroidesC.latidensA dogfish shark.CentrosqualusC.primaevusA dogfish shark.CretascymnusC. adonisA sleeper shark.HarriottaH. lehmaniA long-nosed chimaera.HexanchusH. gracilisA sixgill shark.ParatriakisP. curtirostrisA houndshark.PropristiophorusP. tumidensA sawsharkPteroscylliumP. dubertretiA catsharkP. signeuxi 'Raja'R.'davisiA ray, either a guitarfish or a skate. "Rhinobatos" (gen. nov. 2)R.tenuirostrisA potential relative of the wedgefishes. Likely its own genus."Rhinobatos" (gen. nov. 4)R.intermediusA guitarfish-like ray. Likely its own genus, and its status as a guitarfish is disputed.R. latusScapanorhynchusS. lewisiiA goblin shark.SclerorhynchusS. atavusA sawskate.ScyliorhinusS. elongatusA catshark
Ray-finned fishes Actinopterygians reported from Sahel AlmaGenusSpeciesNotesImagesAcrogasterA. daviesiA trachichthyiform.A. heckeliAlloberyxA. syriacusA holocentriform.A. robustusBenthesikymeB. gracilisA dercetid aulopiform.CharitosomusC. lineolatusA gonorynchid.C. majorCheirothrixC. lewisiiA flying fish-like eurypterygian, possibly an aulopiform.C. libanicusCtenocephalichthysC. brevispinusA holocentriform.C. lortetiDavichthysD. dubiusAn elopid.DercetisD. triqueterA dercetid aulopiform.Dinopteryx D. spinosusA dinopterygid beardfish.DiplomystusD. dubertretiAn armigatid clupeomorph.EnchelurusE. syriacusAn elopomorph sister to eels and notacanthiforms.EnchodusE. majorAn enchodontid aulopiform.E. longidensGnathoberyxG. stigmosusA trachichthyiform.HistiothrissaH.crassapinnaA clupeiform.HoplopteryxH. spinulosusA trachichthyiform.H. syriacusIchthyotringaI. feroxAn ichthyotringid aulopiform.I. furcataI. damoniIstieusI.lebanonensisA bonefish.OmosomaO.intermediumA polymixiid beardfish.O. pulchellumO. sahelalmaeOpistopteryxO. curtusA presumed elopiform.O. gracilisOsmeroidesO. attenuatusA stem-bonefish.O. gracilisO.sardinioidesPantopholisP. dorsalisAn enchodontid aulopiform.ParospinusP. cupulusA holocentriform.PronotacanthusP. sahelalmaeA protostomiid fish (previously considered a spiny eel)Pycnosterinx P. discoidesA polymixiid beardfish.P. dubiusP. gracilisP. russeggeriSardinioides (=Leptosomus)S. macrurusA sardinioidid myctophiform.S. megapterusS. pusillusSpaniodonS. elongatusA euteleost, possibly an osmeriform.S. latusThrissopteroidesT. tenuicepsAn indeterminate teleost, possibly related to Spaniodon.UrenchelysU. avusAn eel.
Invertebrates
Arthropods Arthropods reported from Sahel AlmaGenusSpeciesNotesImagesCarpopenaeusC. garassinoiA carpopenaeid prawn.CirolanaC. cottreauiA cirolanid isopod.C. garassinoiCretasergestesC. sahelalmaensisA sergestid prawn.HamaticarisH. damesiA protozoeid thylacocephalan.KeelicarisK. deboraeA protozoeid thylacocephalan.LoriculinaL. noetlingiA stramentid barnacle.PalaeobenthesicymusP. libanensisA benthesicymid shrimp.PalaeobenthonectesP. arambourgiA benthesicymid shrimp.PalaeognathophausiaP. libanoticaA gnathophausiid crustacean.ProtozoeaP. hilgendorfiA protozoeid thylacocephalan.PseuderichtusP. cretaceusA protozoeid thylacocephalan.PseudodrobnaP. natatorA penaeid prawn.PseudoraninaP. guinotaeA raninid crab.ThylacocephalusT. cymoloposA microcaridid thylacocephalan.
Molluscs Molluscs reported from Sahel AlmaGenusSpeciesNotesImages?BoreopeltisB. smithiA plesioteuthid coleoid, known from a lost specimen.Fuchs; Larson, Dirk; Neal L (March 2011). "Diversity, Morphology, and Phylogeny of Coleoid Cephalopods from the Upper Cretaceous Plattenkalks of Lebanon–Part I: Prototeuthidina". Journal of Paleontology. 85 (2): 234–249.DorateuthisD. syriacaA plesioteuthid coleoid.?GlyphiteuthisG. libanoticaA trachyteuthid coleoid.MuniericerasM.blanfordianumA muniericeratid ammonoid.PalaeoctopusP. newboldiAn octopus.SyrionautilusS. libanoticusA cymatoceratid nautiloid.TexanitesT. texanusA collignoniceratid ammonoid.
References