SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d4ade7164482734666418809e283b4ef602ccbe5c00bdfba6950039eba941c2' 
  AND token = 'TJtp8RcxrKCr26xKtHhTx+60uZj9CFmay5trTVZgjiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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