SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '214aefbbbb2d56717ef46c53219896519122ccf6bd2c9238073feb48833038e2' 
  AND token = 'rSJAotAR8yKVMxIH7MpcUscp8KtrFox4y8FAX+NHH48=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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