SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '13d3cf464676d70600f570535036e7acd28c4e410741234b1f70f184cd90bb42' 
  AND token = '0EVPSfLzruu8po8RDvgrmvpKAylHt8YhL5mA3G71CJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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