SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bc439df85164c37b9a51b537feda5cb327bd43160ba3d84204dd27119cd0c1a' 
  AND token = 'RvU4LptM8oz+/m4VCYRNP5kHG63xqMsEuDf3mlDWhn4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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