SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bff442ecb0396f58309851c7ecc25afb88ae0c066f12ada59ccd8cb55307b7bd' 
  AND token = 'hX45W89PdBg6lxFhpyP57VhS78YEAinqHnOr/VAJdPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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