For dressing, whisk clementine juice, lime juice, vinegar, and salt and black pepper to taste in small bowl. Slowly whisk in oil; set aside.
Arrange salad greens in large serving dish. Top with beets, onion, jicama and clementine sections. Drizzle dressing over salad. Sprinkle with pomegranate seeds, if desired. Season with additional salt and pepper to taste. Serve immediately.