SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '64841df7a3e39423b9453f4c6925df3d963ae0c59e8a5b9fd2a64465990c939e' 
  AND token = '8B5+hqdbYi3sxJUY1sIkjin50h+ww4ptdwACbHnveYE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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