Gradiconus parkeri

Conus (Leptoconus) parkeri (Richards & Harbison, 1947)

Description ⁽¹⁾:

Types observed.–Holotype (USNM 559928; Pl. 17,Figs 9-10): SL 30.0 mm; MD 18.2 mm. Paratype (USNM 559929): SL 27.4 mm; MD 15.8 mm. Both of these type specimens are in very poor condition. An additional paratype (ANSP 16826) was not observed.

Occurrence.–The type specimens were described as being from “Well G.S. #11, 17 miles [27.36 km] west of Boca Raton, Palm Beach County, Florida; depth 47-50 feet [14.3 - 15.2 m]” and were said to have come from the Caloosahatchee Formation (Richards, 1947: 33).

Remarks.–Conus parkeri is only known from the holotype and two paratypes. The holotype (USNM 559928, Pl. 17, Figs 9-10) and paratype closely resemble the extant (and fossil) taxon C. sennottorum Rehder & Abbott, 1951. Similarities with C. sennottorum include a moderately small shell size, a last whorl that is sigmoidal in outline, an angulate shoulder, an asymmetrically curved subsutural flexure, and the presence of incised spiral grooves on the anterior third of the last whorl. The type specimens of C. parkeri, however, are too poorly preserved (for instance, they lack preservation of the protoconch and earliest postnuclear whorls) to justify recognition of the fossil taxon C. parkeri as the senior synonym of the extant taxon C. sennottorum, which was described four years later.

Il Conus pakeri è probabilmente equivalente al Conus sennottorum ⁽¹⁾. Il Conus parkeri è noto solamente per l’holotipo e due paratipi: la mancanza della protoconca e dei primi giri postnucleari non consente di esprimere pareri.

Conus parkeri

Holotype USNM 559928

Well G.S. #11, 17 miles [27.36 km] west of Boca Raton,

Palm Beach County, Florida

depth 47-50 feet [14.3-15.2 m]

Reported as being from the Caloosahatchee Formation

SL 30.0 mm; MD 18.2 mm

Conus parkeri

mm. 26,2 x 14,8

Pliocene – Okeechobee formation

[AZFC N. 229-00]

The "formations" recognized within the latest Tertiary-Quaternary section of southern Florida include:

the latest Pliocene - early Pleistocene Caloosahatchee Formation;

the early Pleistocene Bermont formation (informal);

the late Pleistocene Fort Thompson Formation.

This section consists of fossiliferous sands and carbonates. The identification of these units is problematic unless the significant molluscan species are recognized. Often exposures are not extensive enough to facilitate the collection of representative faunal samples to properly discern the biostratigraphic identification of the formation.

In an attempt to alleviate the inherent problems in the biostratigraphic recognition of lithostratigraphic units, Scott (1992) suggested grouping the latest Pliocene through late Pleistocene Caloosahatchee, Bermont and Fort Thompson Formations in to a single lithostratigraphic entity, the Okeechobee formation (informal).