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AIMS: With our low-resolution spectroscopic observing program for selectedblue proper motion stars, we tried to find new white dwarfs (WDs) in the solarneighbourhood. METHODS: We used the LSPM catalogue with a lower proper motionlimit of 150mas/yr and the UCAC2 for proper motions down to about 90mas/yr. TheLSPM and UCAC2 photometry was combined with Two Micron All Sky Survey (2MASS)near-infrared (NIR) photometry. Targets selected according to their blueoptical-to-NIR and NIR colours were observed mainly at Calar Alto. The spectrawere classified by comparison with a large number of already known comparisonobjects, including WDs, simultaneously observed within our program. Gaia DR2parallaxes and colours were used to confirm or reject spectroscopic WDcandidates and to derive improved effective temperatures. RESULTS: We found tennew WDs at distances between 24.4pc and 79.8pc, including six hot DA WDs: GD221 (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~12.6) and with its Gaia DR2 parallax of ~14masit appears overluminous by about 3mag compared to the WD sequence in the GaiaDR2 colour-magnitude diagram. It may be the closest extremely low mass (ELM) WDto the Sun. We further classified 2MASS J07035743+2534184 as DB4.1. With itsdistance of 25.6pc 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) threeadditional cool WDs were found. Gaia DR2 parallaxes showed us that four of ourcandidates but also two previously supposed WDs (WD 1004+665 and LSPMJ1445+2527) are in fact distant Galactic halo stars with high tangentialvelocities. Among our rejected WD candidates, we identified a bright(G=13.4mag) G-type carbon dwarf, LSPM J0937+2803, at a distance of 272pc.

Spectroscopic classification and Gaia DR2 parallaxes of new nearby white dwarfs among selected blue proper motion stars