Semisulcospira libertina, (GOULD, 1859)

Strong, Ellen E., 2011, More than a gut feeling: utility of midgut anatomy in phylogeny of the Cerithioidea (Mollusca: Caenogastropoda), Zoological Journal of the Linnean Society 162 (3), pp. 585-630 : 612

SEMISULCOSPIRA LIBERTINA (GOULD, 1859)

Material examined

Japan: Shizuoka Prefecture: Inozawa River ( ZMB 102.184 ) .

Description

Marginal fold S-shaped ( Fig. 16B ), terminating at posterior tip of sorting area; oesophageal aperture at tip of marginal fold recurved segment; sorting area elongately triangular, with curving, pointed posterior tip; left margin of sorting area straight; accessory marginal fold curving and bifurcating slightly around left, posterior margin of sorting area; small, wedgeshaped sorting area pad present at left posterior end of sorting area; anterior flap and crescentic pads lacking; glandular pad rather small, flaring posteriorly with broadly rounded posterior end; paired digestive gland ducts opening at left of glandular pad; crescentic ridge long, extending from near oesophageal aperture, curving around posterior end of glandular pad, fusing to side of pad well behind gastric shield above shallow caecum; single, elongate caecal fold opposite posterior glandular pad at right; accessory pads lacking; U-shaped fold present below stylesac aperture; typhlosoles unfused.

Figures

Figure 16. Midgut anatomy of Pleuroceridae (A) and Semisulcospiridae (B). A, Elimia virginica (USNM 1143353). B, Semisulcospira libertina (ZMB 102.184). Scale bars: 1.0 mm; refer to the text for a list of anatomical abbreviations.