Weltnerium nymphocola (Hoek, 1883)

Buhl-Mortensen, Lene & Høeg, Jens T., 2013, Reproductive strategy of two deep-sea scalpellid barnacles (Crustacea: Cirripedia: Thoracica) associated with decapods and pycnogonids and the first description of a penis in scalpellid dwarf males, Organisms Diversity & Evolution (New York, N. Y.) 13 (4), pp. 545-557 : 546

Weltnerium nymphocola

We examined a total of ten specimens W. nymphocola . Eight of them are in the Museum für Naturkunde, Berlin (nos. 6570 and 22251) attached to two individuals of the North Atlantic pycnogonidan sea spider Boreonymphon robustum . One host with three W. nymphocola is shown in Fig. 3a–b , and these specimens were left intact. Six W. nymphocola attached to the other host were detached for detailed examination. This material was also collected by the Deutsche Tiefsee-Expedition, from stn. 7 near Bergen, Norway, (60°37′N, 5°42′W) at 588 m depth and a temperature of 0.8 °C. Two additional specimens, both detached from their host, were kindly lent to us from the Zoological Museum in Bergen, Norway (ZMBN-32774 and ZMBN-15890), from the “Michael Sars” Expedition (66° 42′N, 26° 40′W), taken at 550 m depth, and the “Armauer Hansen” 1914 Expedition (62°15′N 0°15′E), taken at 800 m depth, respectively. Specimens in situ on host crabs were macro-photographed using the macro-optics of an Olympus C5050 camera. Individual barnacle specimens were photographed with a Leica MZ dissection microscope, using either an Evolution® camera or the same Olympus C5050 fitted with an ocular tube adapter. Macro-photography was done using specimens immersed in 70 % alcohol. Cyprids and dwarf males were dissected free and photographed under a dissecting microscope. Specimens used for scanning electron microscopy (SEM) were dehydrated in alcohol and acetone and critical-point dried from liquid CO 2. They were then mounted on stubs with double adhesive tape, sputtercoated with palladium, and examined in a JEOL JSM-6335 F scanning electron microscope. Photo plates were constructed using CorelDraw® or Adobe Photoshop®.

We recorded the numbers of scalpellid specimens attached to a particular host, and the position, orientation, and length of the capitulum of each. By opening the specimens to expose the mantle cavity, we also recorded the number and detailed position of the dwarf males. We also checked all these specimens for the presence of a penis to ascertain whether they were hermaphrodites or females. In ovigerous individuals we measured the brood size and the size range of embryos or brooded larvae.

Figures

Fig. 3 Size distribution of V. brachiumcancri on host R. hertwigi, host id corresponds to Table 1