Chlamys liltvedi H. P. Wagner, 1984
WAGNER, H. P. 1984. Chlamys liltvedi n. sp. (Pectinidae), a new species from South Africa. Basteria, 48: 3-6, figs. 1-6. [p. 3, figs. 1-4]
Chlamys (Chlamys) liltvedi spec. nov.
figs. 1-4 Chlamys squamosa - Barnard, 1964: 420 1974: 761. Not Gmelin, 1791.
The shell is higher than wide. Dimensions, up to 56.5 mm high, 50.0 mm wide and 13.5 mm deep. The valves are inequilateral, the left valve is more swollen than the right one. There are 9-13 pronounced ribs on the left valve, and 22-26 less pronounced ribs in between the major ribs and near the lateral edges of the shell. On the right valve there are 22-32 pronounced ribs and 10-15 less pronounced ribs in between the major ribs and near the lateral edges of the shell. There are squamae on all pronounced and less pronounced ribs. The microsculpture of the valves consists of smooth riblets in the interspace of the major and minor ribs.
Initially there is no microsculpture on the top, but soon the ribs gradually begin to appear at different distances from the apex. The microsculpture of the juvenile area consists of grooves that later on disappear when the riblets mentioned above begin to appear. The anterior ears are 1.5 times as large as the posterior ones. There are 4 ribs on the anterior ear of the right valve and 8-10 on the left valve. There are 6 ribs on the posterior ear of the right valve and 6-8 on the left valve. Except for the ribs of the anterior ear of the right valve, all ribs have squamae. In the byssal notch 6-7 teeth are observed. The byssal notch is to 8.4 mm-deep. Resilium dimensions are 3.1-3.3 mm high and 1.6-1.8 mm wide. The top angle is 80°-85°. The shells are bright orange, with darker and lighter shades of the same colour, yellow with brown, red with darker shades of the same colour and purple with brown, yellow and white near the top. Muscle insertions on the inside of the valves are not visible. Type locality. – Sodwana Bay, Zululand, South Africa, at a depth of 18 m under rocks on reef, covered with sponges, leg. W. R. Liltved. Type material. – Holotype SAM¹ 35885 (1 complete specimen), paratype SAM 35886 (1 complete specimen), paratype W. R. Liltved colln. (1 complete specimen), paratype H. P. Wagner colln. no. 1000 (1 complete specimen), paratype C. M. Connolly colln. (1 leftvalve). Remarks. – Together with the holotype another three specimens were collected. The number of ribs varies as compared to that of the holotype shell, but the right valves have almost twice as many pronounced ribs as the left valves. In the collection of Mrs. Connolly there is a purple-brown beach valve of this new species, found at Durban, Natal. This new species is named in honour of Mr. Billy Liltved. Discussion. – This species is most probably the one identified as Chlamys (Chlamys) squamosa (Gmelin, 1791) by Barnard (1964 420;1974 761). The right valve of C. squamosa is more swollen than the right valve of C. liltvedi. lt is also easy to see the difference in pronounced and less pronounced ribs in C. liltvedi, while the ribs of C. squamosa are all less pronounced. Both species do have riblets in the interspaces, but those of C. squamosa are more prominent. ln C. liltvedi the ribs appear gradually and are clearly visible, soon after the apex is formed; in C. squamosus the ribs do appear in the same way, but are only faintly visible for at least a quarter of the height of the shell. The anterior ears of C. squamosa are longer than those of C. Iiltvedi and all ears of C. squamosa lack squamae; the ribs on the ears are also less pronounced in C. squamosa than in C. liltvedi. C. liltvedi is, as far as known, restricted to the coasts of Zululand and Natal, while C. squamosa is only known from the shelf seas between Japan and North Australia, and from Singapore to Samoa (see also Waller, 1972 224, 239). Material of the latter species was studied in the RMNH (27 complete specimens, 1 left and 2 right valves) and in the author's collection (no. 761, 10 complete specimens). The author is much indebted to Mr. Billy Liltved and to Mrs. Clarice Connolly (Kenwyn, South Africa) for the loan of material and to Dr. A. C. van Bruggen of Leiden University for critically reading the manuscript.» ¹ Abbreviations: SAM = South African Museum, Cape Town; RMNH = Rijksmuseum van Natuurlijke Historie, Leiden.
HOWARD-PAUL WAGNER, 1984
|
H. P. Wagner, 1984, figures 1-4.
|