SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7653f55cb897ee86573c85e931064d2830cfeab9d1b75438126bef377e666de1' 
  AND token = 'smA56HR7tut3pdTIh9Pm0m91UyXHYeW22br9PLr25Dg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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