SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c8f43c9f3901c9e48954177d3a9b5fbb201196aa3ec686700ea533faa33249c' 
  AND token = 'C83jJSIyAQoA6IvIkHXqoOQ9NeZP83zAq2tp5hBQNlc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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