SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ae771af53ea17903802a3b196783fe32f013ff391fc4b256ccabf0a99929f47e' 
  AND token = '4pMrlBTvDLXhaZfx/I3CE+4tHmt7oEWvQGI9Nlmesmo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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