SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce13e4ce85cdb2fc4573a2722899351e5dacef3d8ed0f65a9a540844ba9ecfe0' 
  AND token = 'ZZZQnF9K3+YknNQd8vSQc74DwiyUnzuMQmUI0J+jUOM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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