SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b9a2dbc20b4f24423f5355af1dc6fc24c2787daacc95b73d1d70518d580a909e' 
  AND token = '4VNgduTaxgQbcemMA3qOI5aLf0XEm5FLk9qRRtTZ+vw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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