Carychium floridanum G. H. Clapp, 1918

Jochum, Adrienne, Bochud, Estee, Haberthuer, David, Lee, Harry G., Hlushchuk, Ruslan & Portell, Roger W., 2023, Fossil Carychiidae (Eupulmonata, Ellobioidea) from the Lower Pleistocene Nashua Formation of Florida, with the description of a new species, ZooKeys 1167, pp. 89-107 : 89

publication ID	https://dx.doi.org/10.3897/zookeys.1167.102840
publication LSID	lsid:zoobank.org:pub:6E397DD6-7B6B-4837-BF0C-5C84720DCF55
persistent identifier	https://treatment.plazi.org/id/A5A9E77D-8592-5E97-9C4D-A11BDD6722A1
treatment provided by	ZooKeys by Pensoft
scientific name	Carychium floridanum G. H. Clapp, 1918
status

Treatment

Carychium floridanum G. H. Clapp, 1918 View in CoL View at ENA

Figs 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6 , 7 View Figure 7 , 8 View Figure 8

Carychium exiguum floridanum G. H. Clapp, 1918: 73-75, pl. 8.

Carychium floridanum G. H. Clapp, 1918: Weigand et al. 2013: 3, fig. 1 24|C5; Seq. ID: BARCA032-10, BARCA033-10, BARCA034-10, BARCA035-10, BARCA037-10.

Carychium floridanum G. H. Clapp, 1918: Jochum et al. 2017: 110-111, figs 6, 7.

Material examined.

USA, Florida • Orange County, Orlando ; 28.4489, -81.0375 (WGS84) encompassing 500 m radius; Oct. 2021; R. Portell and H. Means leg.; NMBE 577015-577016 (2 fossil specimens) (Figs 4 View Figure 4 - 6 View Figure 6 ) GoogleMaps .

The two shells were compared to the syntype shell from Snapper Creek Hammock, Miami, FL (CM 46540) presented in Jochum et al. (2017, figs 6, 7) and additionally, to a Recent shell from the Wakulla Springs, FL population [NMBE 572256 (ex. AJC 1446)] [ Weigand et al. 2013, Evolutionary Lineage (EL) C5] (Figs 7 View Figure 7 , 8 View Figure 8 ).

Stratigraphic occurrence.

Freshwater Marl Bed (middle nonmarine layer) Florida Museum of Natural History Invertebrate Paleontology (FLMNH IP) locality OR022, Lower Pleistocene Nashua Formation.

Description.

Shell medium-sized for genus (SH: 1.6-1.8 mm), pupiform in shape, glossy; teleoconch with occasional, fine threadlike ribs, with 4.5-5 tumid whorls. Suture deep. Protoconch smooth, bulbous, shiny, and distinct from teleoconch. Whorl profile strongly convex, aperture higher than wide, elliptical, with 2 barriers, parietal robust with the columellaris constituting a low swollen hump deep in the shell. Peristome doubled and heavily callused, expanded in palatal, basal and columellar regions; largely reflected at the base. Palatal lip weakly sigmoid and buttressed with heavy callus inside and marked with a concavity or line at mid-section behind the apertural rim, extending 2/3 the body whorl in aperture facing left profile view (clearly visible on the grey shell and not detectable on the yellowish one) (Fig. 4 View Figure 4 ). PH 38% of SH. The upper palatal part of the peristome is narrower causing the callused mid-section to project beyond the apertural rim (in aperture facing left view). Umbilicus rimate (Figs 5D View Figure 5 , 6D View Figure 6 ). Internally, a single lamella spirals down the columella for at least the last whorl and a half, terminating in the parietalis of the aperture, which is partially visible and positioned near the columellar side of the inner margin of the peristome in umbilical view (Figs 5C View Figure 5 , 6C View Figure 6 ). The lamella is concave, broadly expanded and wing-like, and strongly flexes down immediately before the aperture, forming the robust parietalis (Figs 5A, E View Figure 5 , 6A, E View Figure 6 ). The surface of the lamella is broad (in dorsal view) with the edge sloping slightly oblique to the columella, flipping over forming a thickened, tongue-like structure in aperture facing right view (Figs 5B, D View Figure 5 , 6B, D View Figure 6 ). The early lamella starts tightly spiraling down the columella at about 2/3 the height of the penultimate whorl (Figs 5B View Figure 5 , 6B View Figure 6 ), expanding rapidly to its fullest winged extension in the middle of the penultimate whorl (Figs 5A View Figure 5 , 6A View Figure 6 ). The callused swollen peristome is flush with the convexity of the penultimate whorl in aperture facing left view (Figs 5E View Figure 5 , 6E View Figure 6 ). The regularly coiled spire is broad with the penultimate whorl expanding almost completely over the body whorl in apical view (Figs 5F View Figure 5 , 6F View Figure 6 ).

Measurements.

SH = 1.6-1.8 mm; SW = 0.81-0.92 mm; PH = 0.60-0.7 mm; PW = 0.61-0.67 mm (N = 3).

Occurrence.

A frequent find in the bulk samples of the Freshwater Marl Bed (middle nonmarine layer).

Living C. floridanum are known today from central Florida up to Wakulla Springs ( Weigand et al. 2013). Earlier collections at the beginning of the 20th century extended as far south as the type locality of Miami in Dade County and in southwestern Florida at Cape Sable, Monroe County ( Clapp 1918). Though human encroachment, canalization practices and habitat modification have severely impacted its occurrence in southern Florida, the paucity of recent records in south Florida is likely the result of limited sampling and not extirpation of the species in this part of the state.

Recent material for comparison.

Carychium floridanum G. H. Clapp, 1918, Wakulla Springs, Wakulla County, FL; 30.2355, -84.3031; BARCA032-10; [NMBE 572256 (ex. AJC 1446)] (N = 1) ( Weigand et al. 2013) (Figs 7 View Figure 7 , 8 View Figure 8 ) GoogleMaps .

Description and comparison.

Shell pupiform, translucent with fine threadlike ribbing on the teleoconch. 4.5 tumid whorls. Aperture elliptical with 2 barriers; parietalis points downwards and columellaris is stronger than in the fossil shells. The fossil shells show greater whorl convexity and a bulbous protoconch. Peristome unevenly shaped and thickly callused, parietal shield more extensive than in fossil shells. Measurements (NMBE 572256): SH = 1.67 mm; SW= 0.84 mm; PH = 0.68 mm; PW= 0.65 mm.

Remarks.

Considering that C. floridanum is clearly genetically and morphologically distinct from its SE North American congeners [EL C5 in Weigand et al (2013)], the internal morphology of the northern Wakulla Springs material is congruent with that of the fossil shells here but not fully congruent with that of the southern syntype material (CM 46540) in Jochum et al. (2017). The possibility that the Wakulla Springs population and the fossil shells in this study could instead constitute a northern-central Floridian lineage designated C. floridanum by Weigand et al. (2013) has yet to be investigated. Ultimately, until genetic data from C. floridanum from southern Florida is available to prove otherwise, we maintain that the fossil and the Wakulla Springs members are C. floridanum .