SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a96582cc8032522140e6261e8c85e727800d0df27ab94eb5a4e6b996751ed9f0' 
  AND token = '826QbfITBxsCbUnMCXhpEwEZOTu3/6itMaZlCXwbrBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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