SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33711e6c3b350cf7f66303e2978a791b5301b6a6c4e0b16ec942bafb2db07737' 
  AND token = 'QtF1oaf66TmejibyivmiCzqOMPbH0M1tWU0UjkHdD7A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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