We are talking about names of species, genera, tribes, families, orders, classes, and phyla. According to the International Code of Zoological Nomenclature, these names are to be treated as Latin names. [We are not talking about Latin words that have been adopted into English (SECTION 4) or about abbreviations of Latin words adopted into English (SECTION 5).
In English-speaking countries (Australia, Canada, New Zealand, South Africa, UK, USA, etc.) 3 systems of pronunciation are used by students:
1. If, in the last 50 years, you have taken a Latin course, you pronounce the name as you were taught to pronounce Latin. Because Latin is a "dead" language, the pronunciation is that which linguists think is closest to the original -- and, unsurprisingly, it is close to the pronunciation of Italian, Portuguese, and Spanish. (This system is at least very similar to the way that Latin is NOW taught in countries where the national language is French, German, Italian, Portuguese, Spanish, etc.).
2. If you never had a Latin course, you perhaps go by the pronunciation given in Borror et al. (An Introduction to the Study of Insects) -- but what you see there is a corrupted Latin pronunciation which was taught in English-speaking countries up to as late as the 1940s. Nobody teaches this kind of Latin pronunciation now. This pronunciation, especially of the vowel sounds, is now considered WRONG by Latin teachers, and is VERY hard to understand by people who learned Latin in non-English-speaking countries.
3. Otherwise, you pronounce scientific names the way that your biology teacher/professor or your boss pronounces them, however wrong that may be. Maybe this cannot be considered a system. At least you can communicate with a few people.
The best solution would be to dump system 2 as soon as possible and to adopt system 1. Meanwhile, you should be aware of the system 1 pronunciation below:
|a (short) as in apple||b (as in English)|
|a (long) as in father||c as in cat|
|e (short) as in get||ch as English k (or k-h)|
|e (long) as in they||d (as in English)|
|i (short) as in pit||f (as in English)|
|i (long) as in machine||g as in go|
|o (short) as in not||h as in hence|
|o (long) as in note||i (consonant i [= j]) as y in yes|
|u (short) as in full||k (as in English)|
|u (long) as in brute||l (as in English)|
|y as "ew" in few but without any trace of y sound||m as in man|
||n (as in English)|
|ae as y in try||ph as English p (or p-h)|
|au as ou in house||q as in quite|
|ei as in rein||r always rolled|
|eu as "ay-oo" (stress the "ay")||s as in sister|
|oe as oi in foil||t as in tanned|
|ui as "we"||th as English t|
|v as English w|
|x as in six|
|z as in zero|