Limatula Wood, 1839

Oliver, P. Graham & Holmes, Anna, 2004, Cryptic bivalves with descriptions of new species from the Rodrigues lagoon, Journal of Natural History 38 (23), pp. 3175-3227 : 3192-3193

publication ID	https://doi.org/ 10.1080/00222930410001695123
persistent identifier	https://treatment.plazi.org/id/03B33A71-5626-FF93-36CD-DA0116F3FEBF
treatment provided by	Felipe
scientific name	Limatula Wood, 1839
status

Treatment

Genus Limatula Wood, 1839 View in CoL

Type species: Pecten subauriculata Montagu, 1808 .

Limatula cf. kinjoi Hayami and Kase, 1993 View in CoL

( figures 66–69 View FIGS )

Limatula kinjoi Hayami and Kase, 1993: 75–76 View in CoL , figures 253–256.

Material examined. Five valves (two gold-coated) from Grand Pate´, off Port Mathurin, shell gravel, 17 m, NMW.Z.2001.061.00020.

Measurements (mm, L 6 H). 0.79 6 1.12, 1.12 6 1.61, 1.43 6 2.16, 0.84 6 1.14.

Description. Illustrated shell is 1.8 mm long and 2.6 mm in height. Equivalve. Slightly opisthocline. Oval subauriculate. Dorsal margin straight, anterior and posterior margins gently curved to ventral margin which is very rounded. Auricles relatively wide. Hinge with provincular teeth on a thin hinge plate and a small, median, triangular ligament pit. Sculpture consists of 22 widely spaced, somewhat carinate, ribs. Concentric growth lines are clearly visible. The prodissoconch is relatively large, 245 M m in diameter, has a large collar and raised apex with a depressed centre (hat-shaped), apex with a deeply pitted microsculpture. The early part of the dissoconch has a more bold sculpture and is demarcated by strong growth stop and may represent a second prodissoconch. Shell is opaque and white in colour.

Comparisons. Most Limatula species do not possess a collared hat-shaped prodissoconch and this character excludes those Indian Ocean taxa considered by Kilburn (1998). Hayami and Kase (1993) considered their L. kinjoi to be the then only known Limatula with a hat-shaped prodissoconch. The Rodrigues material is very similar to Limatula kinjoi with the only difference being the early dissoconch sculpture which is divergent in the Japanese shells but radial in the Rodrigues shells. With so little material available to us we are not prepared to consider this difference to be significant.