SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7139f3674ce823017019740774bd6d62b8dbd8485ca6ac7a57dc4eef0ab0339f' 
  AND token = 'KFrNiYreMsM8OmwsupWVu5Afj240/8PjJwQqlPYa8pQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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