SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7817adc11469c720f09dd03e41651f961bc5ab3b1e1b4986a9899d1542a8e98d' 
  AND token = 'RG/RcBU1l25g4kfroTVN7R4G34WywWLZ0DSCyqLCsfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

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