SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ff032efded2f75dd1e38534c249a3c2a632e050332c3fee50fb8a82a778a228d' 
  AND token = 'FQQsbAuyJt5dyj+s3O0NTBtEXOfEEuUdaqYvg8R9BT0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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