SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c5c9d91d580f4a5dff5db93ef42fb9b63665100b89980f73022e892b2cffa531' 
  AND token = 'soSmKlLR7PgMCugUGe400v6JZO47u8/dR/kHhHmp1/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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