SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'fa62dfee96aac8d504192ab93155a1ea542f81573f16e7729c7acf4469c98da2' 
  AND token = 'NFMOYPr2oFvfZmSWHHYfOtKgTErajj7h/VB+7IBUyKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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