SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bce4e7e9b4fd5932f45262bf643c011b0fb1a6e998c9b7c98365421c869d44f' 
  AND token = 'SP0+7uPwBsnQua0CQOltNwaq7bo08DgcpeGAuCh3XzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

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