Hawkwing Conch
Strombus raninus (Gmelin, 1791)
I found my first Hawkwing Conch in Late November 2020 about a month after I began collcting shells. First I found a wing and the next day, the whole conch. Since then (by the end of January 2021) I have found about a dozen complete versions and several juvenile shells.
Two Hawkwing Conchs from S. Hutchinson Island December 2020
The following are juvenile Hawkwing conchs:
Harry Lee explains:
"Like all members of the family Strombidae, the Hawkwing Conch has determinative growth; all of the shells in the top row belong to that species. This is the same prInciple as manifest in the cowries; juveniles look quite different from adults, which are characterized by a modified outer lip. An old friend used to call the "wingless" specimens "phony conus." He gave at talk on this imposture at a New York Shell Club when I was in med school. There were dozens of species "before and after" depicted on his slides (diapositives in those days). Take a look at <Strombus alatus | letstalkseashells (wixsite.com)>, which includes images of young shells. The attached is a scanning electron micrograph I made of a fossil Fighting Conch which expired when it was a 1/15 inch baby."
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Lobatus raninus
From Wikipedia, the free encyclopedia
Scientific classification edit
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Caenogastropoda
Order: Littorinimorpha
Family: Strombidae
Genus: Lobatus
Species: L. raninus
Binomial name
Lobatus raninus
(Gmelin, 1791)
Synonyms[1]
List of synonyms
Lobatus raninus, common name the hawk-wing conch, is a species of medium to large sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.[1]
Shell description
A drawing depicting the shell of Lobatus raninus from Index Testarum Conchyliorum (1742).
The maximum recorded shell length is 121 mm[2] or up to 130 mm.[3] Like other species in the same genus, Lobatus raninus has a robust, somewhat heavy and solid shell, with a distinct stromboid notch. The body whorl is dorsally ornamented by characteristic coarse spiral ridges.[3] The posterior expansion of the flaring outer lip is always lower than the spire.[3] The color is brownish, with several disperse white spots. Both inner and outer lips are cream or white.[3]
Phylogeny
Strombidae
Terebellum terebellum
Canarium urceus
Conomurex luhuanus
Tricornis raninus
Lambis lambis
Strombus
Eustrombus
Aliger
A simplified version of the phylogeny and relationships of Strombidae according to Simone (2005)[4]
Strombus gallus
Strombus gigas
Strombus costatus
Strombus raninus
Strombus peruvianus
Strombus galeatus
Strombus latus
Strombus pugilis
Strombus alatus
Strombus gracilior
Strombus granulatus
Phylogeny and relationships of Eastern Pacific and Atlantic Strombus species, according to Latiolais and colleagues (2006)[5]
The phylogenetic relationships among the Strombidae have been mainly accessed on two occasions, using two methods. In 2005, Simone proposed a cladogram (a tree of descent) based on an extensive morpho-anatomical analysis of representatives of Aporrhaidae, Strombidae, Xenophoridae and Struthiolariidae, including L. raninus (there referred to as Tricornis raninus).[4]
With the exception of Lambis and Terebellum, the remaining taxa were previously allocated within the genus Strombus. However, according to Simone, only Strombus gracilior, Strombus alatus and Strombus pugilis, the type species, remained within Strombus, as they constituted a distinct group based on at least five synapomorphies (traits that are shared by two or more taxa and their most recent common ancestor).[4] The remaining taxa were previously considered as subgenera, and were elevated to genus level by Simone in the end of his analysis. The genus Tricornis (now considered a synonym of Lobatus),[1] in this case, only included T. raninus (now considered a synonym of Lobatus raninus).[1][4]
A different approach, this time based on sequences of nuclear histone H3 and mitochondrial cytochrome-c oxidase I (COI) genes was proposed by Latiolais et al. (2006). The phylogenic relations of (32 analyzed) species that used to belong or still belong in the genus Strombus and Lambis are shown below:[5]
Distribution
This species is distributed in the Caribbean Sea, the Gulf of Mexico and the Lesser Antilles.
Ecology
Habitat
S. raninus lives near seagrass beds, usually in shallow water.[3] The minimum recorded depth is 0.3 m; the maximum recorded depth is 55 m.[2]
Feeding
Like other species of the genus Strombus, S. raninus is known to be a herbivore.
References
Bouchet, P. (2010). Lobatus raninus (Gmelin, 1791). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=531851 on 2011-03-21
Welch, J.J. (2010). "The "Island Rule" and Deep-Sea Gastropods: Re-Examining the Evidence". PLoS ONE 5(1): e8776. doi:10.1371/journal.pone.0008776.
Cervigón, F. et al. (1993). "FAO species identification sheets for fishery purposes. Field guide to the commercial marine and brackish-water resources of the northern coast of South America". Rome, FAO. 513 p.
Simone, L. R. L. (2005). "Comparative morphological study of representatives of the three families of Stromboidea and the Xenophoroidea (Mollusca, Caenogastropoda), with an assessment of their phylogeny" (PDF). Arquivos de Zoologia. São Paulo, Brazil: Museu de Zoologia da Universidade de São Paulo. 37 (2): 141–267. ISSN 0066-7870. Archived from the original (PDF) on 2012-03-05.
Latiolais J. M., Taylor M. S., Roy K. & Hellberg M. E. (2006). "A molecular phylogenetic analysis of strombid gastropod morphological diversity". Molecular Phylogenetics and Evolution 41: 436-444. doi:10.1016/j.ympev.2006.05.027.PDF.
Rosenberg, G., F. Moretzsohn, and E. F. García. 2009. Gastropoda (Mollusca) of the Gulf of Mexico, Pp. 579–699 in Felder, D.L. and D.K. Camp (eds.), Gulf of Mexico–Origins, Waters, and Biota. Biodiversity. Texas A&M Press, College Station, Texas