Context :

Aims : With our low-resolution spectroscopic observing program for selected blue proper motion stars , we tried to find new white dwarfs ( WDs ) in the solar neighbourhood .

Methods : We used the Lépine & Shara Proper Motion ( LSPM ) catalogue with a lower proper motion limit of 150 mas/yr and the Second US Naval Observatory CCD Astrograph Catalog ( UCAC2 ) for proper motions down to about 90 mas/yr .
The LSPM and UCAC2 photometry was combined with Two Micron All Sky Survey ( 2MASS ) near-infrared ( NIR ) photometry .
Targets selected according to their blue optical-to-NIR and NIR colours were observed mainly at Calar Alto .
The spectra were classified by comparison with a large number of already known comparison objects , including WDs , simultaneously observed within our program .
Gaia DR2 parallaxes and colours were used to confirm or reject spectroscopic WD candidates and to derive improved effective temperatures .

Results : We found ten new WDs at distances between 24.4 pc and 79.8 pc , including six hot DA WDs : GD 221 ( DA2.0 ) , HD 166435 B ( DA2.2 ) , GD 277 ( DA2.2 ) , 2MASS J19293865+1117523 ( DA2.4 ) , 2MASS J05280449+4105253 ( DA3.6 ) , and 2MASS J05005185-0930549 ( DA4.2 ) .
The latter is rather bright ( G \approx 12.6 ) and with its Gaia DR2 parallax of \approx 14 mas it appears overluminous by about 3 mag compared to the WD sequence in the Gaia DR2 colour-magnitude diagram .
It may be the closest extremely low mass ( ELM ) WD to the Sun .
We further classified 2MASS J07035743+2534184 as DB4.1 .
With its distance of 25.6 pc it is the second nearest known representative of its class .
With GD 28 ( DA6.1 ) , LP 740-47 ( DA7.5 ) , and LSPM J1919+4527 ( DC10.3 ) three additional cool WDs were found .
Gaia DR2 parallaxes showed us that four of our candidates but also two previously supposed WDs ( WD 1004+665 and LSPM J1445+2527 ) are in fact distant Galactic halo stars with high tangential velocities .
Among our rejected WD candidates , we identified a bright ( G = 13.4 mag ) G-type carbon dwarf , LSPM J0937+2803 , at a distance of 272 pc .

Conclusions :