SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7d8a33e6d60cb207bb8a147e660a36204610f49f53c8df02067dae1aec28d86' 
  AND token = 'NlcUEFH+D6lkDwqP9YVkay5hwjKedFgc3LhGspG5tdc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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