SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03ccc3c34945477eaeabf2312280b06b34355ecbffd01b5692272045849693fa' 
  AND token = '7STaksm5px7yVDTJ+2o+G+qFJR3vhrSZ9OgV0xhqEzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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