SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fff44ec9b3d9a42997184cb131bdaac443c0c23a1fd09145c3b570c2c7f1967' 
  AND token = 'FewcBF0QzQDBDNTlx/89gMfmwAiTGt3TbiCiaF9DEmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}