SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a52bf2992e5238cc7f23c9c38f46a182c72ce6284ac847b78c35d7b21f3df8fe' 
  AND token = 'ZnKWc16h638pPGOljHh7eafW8cgjQpNzFsLkn6EKas4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}