Jump to content

isurolamna inflata vs affinis


will stevenson

Recommended Posts

will stevenson

Hi guys, would anyone know the difference between isurolmna affinis and inflata, i cant seem to find an age gap and physically their features, to me at least, seem very similiar

anyway, the reason i am asking as i have read conflicting resources on teeth from unit J of upnor fm (beltinge fish bed) at herne bay, UK that differ between one and the other and im not sure which to go with, thanks for your help:)

Link to post
Share on other sites

The below excerpt is from elasmo.com.  I don't know if this helps because it is confusing to me.

 

"Lamna vincenti var inflata was described by Leriche (1905:76) from late Ypresian, and from the early Middle Eocene of Belgium (1905:125). As it was only a variety of "Lamna vincenti = "Lamna" lerichei (CASIER 1946) it was not figured. It was first figured (as Lamna vincenti var inflata) in Leriche (1908:11, Pl. 1, fig. 9) for a tooth in the Bories collection from the Early Lutetian of Fontas, near Fabrezan, in the Corbières region SW France. The tooth, Leriche suggested, was a first upper right anterior. This tooth may actually be the second upper and the horizon may prove to be Late Ypresian (NP 12, not Lutetian). The name was used as a species, as opposed to a variety, by Leriche in 1936 (Leriche 1936a: 296) in a paper on reworked basal Oligocene teeth from NE Holland. This was the same year as he again published on teeth from the Corbières (Leriche 1936b: 398, 399).

 

Odontaspis hopei form affinis CASIER 1946 was based on lower anterior teeth from the late Ypresian, in the region of the NP12 of Belgium. "affinis" was first used as a species, "Lamna affinis", by Casier in 1950. Cappetta (1976: 555) erected the genus Isurolamna, and made Casier's Odontaspis hopei form affinis the type without mention of the species "inflata". However, in 1987, in the Handbook of Paleoichthyology, Cappetta referred "inflata" to Isurolamna, suggesting that it (inflata) ranged from Thanetian (Palaeocene) to the Ypresian (Early Eocene).

 

As noted earlier, Leriche originally described inflata from the Early and Middle Eocene. As both "species" were described from more or less strata of the same age and geographic region, inflata must be the senior synonym, having been described 41 years earlier. Cappetta suggested that affinis probably branched from inflata (Cappetta 1987: 95). This implies that both affinis and inflata co-existed in the Palaeocene or Early Eocene -- there is no published or personally observed evidence of this."

 

Marco Sr.

  • I found this Informative 2
Link to post
Share on other sites
will stevenson
7 hours ago, MarcoSr said:

The below excerpt is from elasmo.com.  I don't know if this helps because it is confusing to me.

 

"Lamna vincenti var inflata was described by Leriche (1905:76) from late Ypresian, and from the early Middle Eocene of Belgium (1905:125). As it was only a variety of "Lamna vincenti = "Lamna" lerichei (CASIER 1946) it was not figured. It was first figured (as Lamna vincenti var inflata) in Leriche (1908:11, Pl. 1, fig. 9) for a tooth in the Bories collection from the Early Lutetian of Fontas, near Fabrezan, in the Corbières region SW France. The tooth, Leriche suggested, was a first upper right anterior. This tooth may actually be the second upper and the horizon may prove to be Late Ypresian (NP 12, not Lutetian). The name was used as a species, as opposed to a variety, by Leriche in 1936 (Leriche 1936a: 296) in a paper on reworked basal Oligocene teeth from NE Holland. This was the same year as he again published on teeth from the Corbières (Leriche 1936b: 398, 399).

 

Odontaspis hopei form affinis CASIER 1946 was based on lower anterior teeth from the late Ypresian, in the region of the NP12 of Belgium. "affinis" was first used as a species, "Lamna affinis", by Casier in 1950. Cappetta (1976: 555) erected the genus Isurolamna, and made Casier's Odontaspis hopei form affinis the type without mention of the species "inflata". However, in 1987, in the Handbook of Paleoichthyology, Cappetta referred "inflata" to Isurolamna, suggesting that it (inflata) ranged from Thanetian (Palaeocene) to the Ypresian (Early Eocene).

 

As noted earlier, Leriche originally described inflata from the Early and Middle Eocene. As both "species" were described from more or less strata of the same age and geographic region, inflata must be the senior synonym, having been described 41 years earlier. Cappetta suggested that affinis probably branched from inflata (Cappetta 1987: 95). This implies that both affinis and inflata co-existed in the Palaeocene or Early Eocene -- there is no published or personally observed evidence of this."

 

Marco Sr.

thanks Marco, what I take from this is it's hard to know which species it is

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...