SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00cbfb5fb99ccb190bd88792f16099407ef00c756949d1556ae0792ff8763510' 
  AND token = 'GJGe8S2vuOQlgwfYa5Iga0Xb7XiCbDUej3vzbwIQ4Ss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables