SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '71c120a06d7dcb1eff7e705c9aff30c6be086aa99c60eb4d24b7d918ad43a306' 
  AND token = 'aGGzkJAo2ic/hOU3Vz4R+9/w0KlG9h9VeQy+F1pmkIs=' 
  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