SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '499cc8615698dda680809716dcc06c93b984a7986bcd25078ccca06bde6ad080' 
  AND token = 'vWDwipFCR20y+rwX5/KoTS8oQsPPGt5ui6jXFrHQuJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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