Hi :) native English speaker here from England! The first pronunciation is how I would pronounce the word species, this is a typical british accent from the south/centre of England. The second pronunication is definitely more of an upper class british accent and I personally don't pronounce species in this way. I hope this helps! :)

Both recordings are British, but they have different regional accents. I am American, and I pronounce it closer to #1.

Like Ian, I also pronounce it as number 1. Both pronunciations are correct on both sides of the pond. This is not a matter of accent — it’s a matter of two different correct pronunciations. As far as the recording, both speakers have almost the same British accent (relatively close to RP, especially the second speaker). According to the relevant Wikipedia article, only about 3-10% of the UK population speak with an RP accent. For your information, the UK has a huge variety of widely divergent different accents — if you think those two sound different, prepare for a shock when you get to London (not to mention Scotland, Wales, and Northern Ireland). By comparison, American / Canadian English is extremely homogeneous.

They’re both British. I’m American and have always pronounced it SPEE-sheez, as do most of the people I know, so I’m not sure where someone above got the idea that that’s a slightly weird pronunciation. And indeed, the American dictionary quoted above agrees with me (by putting that pronunciation first).

I can't believe what they have told you! None are American, both are British. Honestly it makes me mad that people answered without hearing that audio you attached, because any native speaker would know none of them are American. https://voca.ro/1i0c7dLK2K1A this is how I say with an American accent (California) but to say it like speshies is fine too,a bit weirder, but fine. This isn't something that differentiates British from American speakers as you might have realized. But I am an expert of American English and especifically the Californian accent, so if you want to learn with me, I can guide you and tell you how to learn this by yourself!