Litiopa melanostoma, RANG, 1829

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 : 597

LITIOPA MELANOSTOMA RANG, 1829

Material examined

Atlantic Ocean: US: Florida: Marathon Key: Coco Plum Beach , 24°43.45′N, 81°00.04′W ( USNM 1143355 ) .

Description

Marginal fold S-shaped ( Fig. 7C ), curving well past posterior end of sorting area; oesophageal aperture at apex of marginal fold recurved segment; sorting area tapering posteriorly to pointed tip, with ill-defined folds anteriorly; left margin of sorting area with conspicuous bulge; sorting area pad, anterior flap, crescentic pads, and accessory marginal fold lacking; glandular pad forming small, rounded mound projecting short distance posteriorly behind gastric shield; single digestive gland duct opening at left of glandular pad; crescentic ridge forming small diverticulum from posterior end of glandular pad, with proximal tip well posterior to digestive gland duct; accessory pads, caecum, and caecal folds lacking; U-shaped fold present below lip of style sac; typhlosoles unfused.

Remarks

Houbrick (1987b: 13) described the midgut anatomy of litiopids simply as being characterized by, ‘... a large central ridge, a gastric shield, and a short style sac.’

Figures

Figure 7. Midgut anatomy of Litiopidae. A, Alaba monile (USNM 858584). B, Alaba opiniosa (USNM 1084214). C, Litiopa melanostoma (USNM 1143355). D, Styliferina translucida (USNM 1084087). Scale bars: 0.5 mm; refer to the text for a list of anatomical abbreviations.