We present an all-sky catalogue of 395 nearby galaxy groups revealed in the Local Supercluster and its surroundings .
The groups and their associations are identified among 10914 galaxies at |b| > 15 ^ { \circ } with radial velocities V _ { LG } < 3500 km s ^ { -1 } .
Our group finding algorithm requires the group members to be located inside their zero-velocity surface .
Hereby , we assume that individual galaxy masses are proportional to their total K -band luminosities , M / L _ { K } = 6 M _ { \odot } / L _ { \odot } .

The sample of our groups , where each group has n \geq 4 members , is characterized by the following medians : mean projected radius \langle R \rangle = 268 kpc , radial velocity dispersion \sigma _ { V } = 74 km s ^ { -1 } , K -band luminosity L _ { K } = 1.2 10 ^ { 11 } L _ { \odot } , virial and projected masses M _ { vir } = 2.4 10 ^ { 12 } and M _ { p } = 3.3 10 ^ { 12 } M _ { \odot } , respectively .
Accounting for measurement error reduces the median masses by 30 per cent .
For 97 per cent of identified groups the crossing time does not exceed the cosmic time , 13.7 Gyr , having the median at 3.8 Gyr .

We examine different properties of the groups , in particular , of the known nearby groups and clusters in Virgo and Fornax .
About a quarter of our groups can be classified as fossil groups where the dominant galaxy is at least ten times brighter than the other group members .

In total , our algorithm identifies 54 per cent of galaxies to be members of groups .
Together with triple systems and pairs they gather 82 per cent of the K -band light in Local universe .
We have obtained the local value of matter density to be \Omega _ { m } = 0.08 \pm 0.02 within a distance of \sim 40 Mpc assuming H _ { 0 } = 73 km s ^ { -1 } Mpc ^ { -1 } .
It is significantly smaller than the cosmic value , 0.28 , in the standard \lambda CDM model .
The discrepancy between the global and local quantities of \Omega _ { m } may be caused by the existence of Dark Matter component unrelated to the virial masses of galaxy systems .