SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3f695a797c96ed3fbf2107ba9223fd97f4542f97aca9c29dc72a3e8ca61fed4' 
  AND token = 'HdACpeHfC/o9lrI6eudwyGdE/HusTcco/3r2En0AaMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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