SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a231ada300c7000b8bdea550f5bb8dde35c37c7f82aba75b9f58f97ef46a48c0' 
  AND token = 'H33VWecB2cOEtBofk7Ry8UFa7DshizfGLhsjkne0Zqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}