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Velicucullus oddgurneri Bjørklund, 1976

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The genus is characterized by its velum on the underside of the flatly expanded or almost discoidal thorax. Because of the great size of this species, and the flat thorax, it is rather difficult to turn the specimens when mounted on the slide and almost all observations were, on the 25 specimens examined, from the apical side. It was, therefore, not possible to observe the velum in side view. There is a shadow of a ring located on the thorax where the thorax wall starts to flatten out. As there is no stricture in this position, this shadow is taken for being the velum (plate 19, figs. 6-8).
For internal structures, the medial bar with the axial, dorsal, ventral, and lateral bars are recognized. The normal pattern is that these bars are perpendicular to each other (plate 19, fig. 6). The dorsal spine, however, does, in some cases, furcate so it looks as if five spines are present (fig. 18). In some cases, the spines penetrate the thoracic wall, so they can be seen on the outside. The diameter of the outer edge of the flattened thorax varies between 360 and 450µm, while the diameter of what is believed to be the velum varies between 180 and 230µm. The pores on the thorax are irregularly rounded, with an almost uniform size, 8-10µm, showing a tendency to linear orientation towards the rim (pl. 19, fig.8).
Bjørklund 1976











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