I have no idea there are so many different types of jellyfish

[kadioguy]

[In an aquarium]

Campbell: Look at all the jellyfish.
Linda: I think this is my favorite room so far. It's so beautiful and peaceful here.
Campbell: Yeah, there's something very relaxing about watching jellyfish swim.
Linda: Yes. And I have no idea there are so many different types of jellyfish.
---
Why does she say "have" instead "had"?

a. I have no idea there are so many different types of jellyfish.
b. I had no idea there are so many different types of jellyfish. [PS - I think that some people would use "had ... there were ..." though.]

What is the difference in meaning in the context?

[Source]

 

[Phaedrus]

The version with "have" makes no sense: she is denying that she has a certain idea, namely, the idea that she means to express.

 

[kilroy65]

Why does she say "have" instead of "had"?

She actually says "had".