Two trawl samples of natural sunken wood collected near Vanuatu were identified based on histological studies. Detailed descriptions were made and microphotographs of the cell types were taken, using the three classical sections (cross, tangential and radial). The botanical characters were compared first to the native flora of Vanuatu, then also to the introduced species. The possibility of transportation by ocean currents with a mainly southern and eastern direction is discussed. The first sample lacks apparent colonization marks. Its main histologic character is the presence of ‘paedomorphic type I rays’ which relates it to the shrubby genera Fitchia (Asteraceae) and Fuchsia (Onagraceae): both are known in Polynesia but they seem not to be recorded from Vanuatu. The second wood sample is densely colonized by molluscs and other fauna. It comes from a tree close to the Fabaceae‐Mimosoideae, possibly belonging to the genera Leucaena or Serianthes, both known from Vanuatu. Our work shows for the first time that, even after prolonged submergence in water at substantial depth (>500 m), the wood structure may be well preserved. Therefore, the botanical identification and the determination of the origin of the sunken wood were possible. The two selected samples show completely different colonization patterns, which could be related to differences in chemical composition or to time elapsed since sinking.

The sea-grass borer Zachsia zenkewitschi belongs to a group of economically and ecologically important bivalves, commonly referred to as shipworms. The sole recognized representative of the genus Zachsia, this species displays an unusual life history and reproductive strategy that is now understood to include: environmental sex determination of free swimming larvae, extreme sexual and size dimorphism between males and females, internal fertilization, maintenance of often large harems of male dwarfs within a specialized cavity of the female mantle, and complex maternal care of larvae in specialized brood pouches within the gill. It is also the only shipworm species known to burrow in sea grass rhizomes rather than terrestrial wood. Although Z. zenkewitschi is rare and little studied, understanding of its biology and anatomy has evolved substantially, rendering some aspects of its original description inaccurate. Moreover, no existing type specimens are known for this species. In light of these facts, we designate a neotype from among specimens recently collected at the type location, and undertake a re-description of this species, accounting for recent reinterpretation of its life history and functional anatomy.

A major shell matrix protein originally obtained from a freshwater snail is a molluscan homologue of Dermatopontins, a group of Metazoan proteins also called TRAMP (tyrosine-rich acidic matrix protein). We sequenced and identified 14 molluscan homologues of Dermatopontin from eight snail species belonging to the order Basommatophora and Stylommatophora. The bassommatophoran Dermatopontins fell into three types, one is suggested to be a shell matrix protein and the others are proteins having more general functions based on gene expression analyses. N-glycosylation is inferred to be important for the function involved in shell calcification, because potential N-glycosylation sites were found exclusively in the Dermatopontins considered as shell matrix proteins. The stylommatophoran Dermatopontins fell into two types, also suggested to comprise a shell matrix protein and a protein having a more general function. Phylogenetic analyses using maximum likelihood and Bayesian methods revealed that gene duplication events occurred independently in both basommatophoran and stylommatophoran lineages. These results suggest that the dermatopontin genes were co-opted for molluscan calcification at least twice independently after the divergence of basommatophoran and stylommatophoran lineages, or more recently than we have expected.

Often only one or a few individuals of rare species are collected. How do we treat them as intact voucher specimens? The shell of the whole individual in formalin or alcohol will corrode or fade. In order to dissect the soft parts, you must crack or dissolve the shell. Niku-nuki, a traditional method that has been used by Japanese malacologists overcomes this dilemma. It is also applicable to minute molluscs. The outline is: 1. Prepare boiling hot freshwater, a small beaker, forceps (with fi ne tips), a small syringe, a petri dish, and a stereomicroscope; 2. When the live animal in the beaker crawls on the bottom, pour boiling hot water over the animal, which is killed immediately. Some seconds later take the specimen out of the hot water, hold it with two fi ngers of one hand and hold the forceps with another hand; 3. Under the microscope, grab the foot with the forceps and pull carefully to just separate the columellar muscle from the shell; 4. Pull the foot again in a petri dish fi lled with cold water as under 3. With coiled gastropods, unscrew the specimen by approximately ¼ whorls. If it is diffi cult to move the soft parts, inject water into the aperture gently with the syringe. Repeat it several times, then you will get an empty shell and the complete soft parts. With this method, we can obtain intact shells and soft parts for multiple purposes such as conchological observation and gross anatomy. DNA can also be extracted from those soft parts because DNA is stable at high temperature. The boiled animal can be dehydrated in alcohol. We can prevent the negative effect of DNase (by heat) and magnesium (by washing in freshwater) on the DNA.