Let's consider the piano version of Moldau/Vltava from Smetana for the first two measures for example.

[!["Moldau" mm. 1–2 with staccato, accented eighth-note chords circled][1]][1]

[1]: https://i.sstatic.net/US5jE.png

What should be the duration of the blue circled note, expressed in units of eighth note :
should it be *less* than a eighth note, *equal* to one eighth note ?

Is it staccato or something else ?
If this is *less* than a eighth note, then, would it mean that the right circle note do not "fill" the rest of the measure ? (if so, why there is not a sort of silence added on the score ?)