Larval shell development of four species of New Zealand mussels: (Bivalvia, Mytilacea)

Abstract

Larvae of Mytilus cdulis aoteanus, Perna canaliculus, Xenosirobus pulex, and Modiolarca impacta were reared to settlement in the hatchery. A detailed comparative study, based on microscopy (optical and SEM) and morphometry, has been carried out on the four species. External features and the internal hinge structure of the larval shells of the four species show typical mytilid characteristics. Externally, umbo stage larvae of Modiolarca impacta are ovoid in the anterioposterior direction, shell heights are substantially less than lengths, umbones are low and broadly rounded, and the anterior end is more pointed than the posterior. Mytilus edulis aoteanus and Perna canaliculus umbo stage larvae are similar, initially ovoid in the anterioposterior direction and later more rounded with shell heights approximately equal to lengths, umbones broadly rounded. The shoulders of P. canaliculus larvae are higher and more angular than those of M. edulis aoteanus. Xenostrobus pulex larvae are round to ovoid in the dorsoventral direction. Shell heights are equal to or greater than lengths, umbones are knobby. Provinculum lengths and shapes are similar in Modiolarca impacta, M. edulis aoteanus, and P. canaliculus. Provinculum length is shorter and the shape distinctive in X. pulex. The provincular teeth number in larvae 200-299 |am long is 16-24 in Modiolarca impacta, 18-24 in P. canaliculus, 20-30 in M. edulis aoteanus, and 10-15 in X. pulex. The primary lateral hinge teeth in pediveliger stage larvae of P. canaliculus do not develop in the other three species.

Early Stages in Morphogenesis of the Shell of Crenella decussata (Bivalvia: Mytilidae)

“…Larvae were also identified based on the descriptions of larval morphology of mytilid species available in the literature (Jørgensen, 1946;Rees, 1950;Chanley & Andrews, 1971;Le Pennec & Masson, 1976;Booth, 1977;Lutz & Hidu, 1979;Le Pennec, 1980;Redfearn et al, 1986;Fuller & Lutz, 1989;Kasyanov et al, 1998Malchus, 2006;Semenikhina et al, 2008;Evseev et al, 2010). Larval shell terminology is the same as in the foregoing works.…”

Differential effects of adult mussels on the retention and fine-scale distribution of juvenile seed mussels and biofouling organisms in long-line aquaculture

“…early austral spring) because this is typically a period of low primary settlement of P. canaliculus at the study site and therefore our estimates of retention were less likely to be confounded by over-settling conspecifics early in the experimental period. At other times of the year, new cohorts are easy to determine using size and morphological characteristics (Redfearn et al 1986, Atalah et al 2016. Furthermore, the mussel farm used in this study was in 30 m deep water, with the experiment deployed at 4 m depth, while the secondary settlement by wild mussels typically occurs deeper in the water column (Alfaro & Jeffs 2003).…”

Мейоз, эмбриональное и личиночное развитие черноморского гребешка Flexopecten glaber ponticus (Bucquoy, Dautzenberg & Dollfus, 1889) (Bivalvia, Pectinidae)

“…Для изучения строения замка створки личинок очищали от мягких тканей, погружая их на несколько секунд в 5 % раствор гипохлорита натрия (NaOCl), затем промывали в дистиллированной воде с добавлением капли аммония для нейтрализации NaOCl. Для описания промеров раковин велигеров использована терминология из [13] (рис. 1); описание структуры замкового края личинок приведено по З. К. Захваткиной [2].…”