Erica Meltzer Gramma Question PLEASE HELP

I have Erica Meltzer’s SAT Grammar book and one of the fixing sentences questions is:

The roundscale spearfish and the white marlin are two (separate, if closely related, species.)
a) separate, if closely related, species
b) separate species, although being closely related
c) separate species, but also closely related
d) separate species, whereas they are related closely
e) separate species, although their relationship is a close one

The answer is A, but I don’t understand the meaning of the word “if” in this sentence. Does it mean something similar to “but”?

Yep

Another way to say it would be “separate, although closely related, species.”
“If” is there to acknowledge the failings in the word separate, so it is similar to “but,” yes.

  • I know, I know! stretching hand up real high.
  • Yes, gcf?
  • It's an idiom! "if closely related" = "even though closely related"! And it's nonessential! And, and...
    • Good work, gcf; here's your Gold Star sticker. :D

@gcf101 I laughed. thanks :))

@c0llegeb0und2468 Glad it provided a comic relief - SAT prep work can be soul crushing at times…

On unrelated note: while I was polishing off my skit, it grew too old for this thread. Better start working on speed writing!