SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '40a13d97fdaf436f54db1181fe1cd74a506f049973c899dc323e32c3c45f1292' 
  AND token = 'uHPSJFel1IaZmMnSxXr4AZvGYZrpCDNI2QYP0f/MqzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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