SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '53f681523c792a8a8f753b05aa60c239657e7f648bf37aebc63dd4670216221d' 
  AND token = 'yk2FX+dbVpqb3djSlecoFXmC1gCN4MiUr0MA7XrJ2QE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

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