Did Tom Riddle really try to kill Aragog?

Question

Based on the Riddle's diary:

A vast, low-slung, hairy body and a tangle of black legs; a gleam of many eyes and a pair of razor-sharp pincers — Riddle raised his wand again, but he was too late. The thing bowled him over as it scuttled away, tearing up the corridor and out of sight. Riddle scrambled to his feet, looking after it; he raised his wand, but the huge boy leapt on him, seized his wand, and threw him back down, yelling, “NOOOOOOO!”

Harry Potter and the Chamber of Secrets, Chapter 13, The Very Secret Diary

I ask this question because Aragog was a spider and the way a spider kills its victim is different from how Basilisk kills its victim.

Aragog was Acromantula and used poison to kill it's victim

An acromantula is a gigantic black spider (legspan may reach up to 15 feet) with a poisonous bite, the Acromantula is an anomaly in the beast / being classification system.

Harry Potter Lexicon: Acromantula

Basilisk has multiple options, when it came to killing its victim.

Its methods of killing are most wondrous, for aside from its deadly and venomous fangs, the Basilisk has a murderous stare, and all who are fixed with the beam of its eye shall suffer instant death.

Harry Potter and the Chamber of Secrets, Chapter 16, The Chamber of Secrets

We also know from Myrtle, that she was not bitten by Basilisk.

“No idea,” said Myrtle in hushed tones. “I just remember seeing a pair of great, big, yellow eyes. My whole body sort of seized up, and then I was floating away. …”

Harry Potter and the Chamber of Secrets, Chapter 16, The Chamber of Secrets

Aragog had to bite Myrtle to kill her, since the above passage makes it clear that Myrtle was not bitten. Since Aragog was not caught, it became easier for Tom Riddle to blame Aragog (or Hagrid) for Myrtle's death.

“It was my word against Hagrid’s, Harry. Well, you can imagine how it looked to old Armando Dippet. On the one hand, Tom Riddle, poor but brilliant, parentless but so brave, school prefect, model student … on the other hand, big, blundering Hagrid, in trouble every other week, trying to raise werewolf cubs under his bed, sneaking off to the Forbidden Forest to wrestle trolls … but I admit, even I was surprised how well the plan worked. I thought someone must realize that Hagrid couldn’t possibly be the Heir of Slytherin."

Harry Potter and the Chamber of Secrets, Chapter 17, The Heir of Slytherin

But if Tom Riddle had killed (or caught) Aragog, anybody could have investigated the matter further and based on the evidence found out that Aragog didn't kill Myrtle.

Answer 1

Riddle sought a scape goat for the attacks he himself caused. His plan would have been to present Aragog as the culprit and then promptly stop the attacks. I think that having the the attacks stop immediately after a deadly beast was discovered and disposed off, would have been too much of a coincidence for the administration of Hogwarts to ignore. This is compounded by the fact the Riddle knew himself to be virtually (with the exception of Dumbledore) beyond reproach in the eyes of Dippet. Which would make it unlikely that he would suspect Riddle of any foul play.

Furthermore , Hagrid is about 60 years old at the time of the second book (1992) which makes his altercation with Riddle take place at around 1945.

The first edition of Fantastic beast and where to find them is released at 1927, just 18 years before.

As a rule the Wizarding world is quite conservative, so I'd venture the book hasn't proliferated extensively in that time.

It could be argued then, that the methods by which Basilisks and Acrumantuli differ at killing were not widely (if at all) known.