SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84692cecb3cce254d9425bb2b1e1acea7c754e5e6a803a5734974621ede73149' 
  AND token = 'cyYgS12tS0JEm0DSsXCKrl6MFDlDkGd56Ue+ZE5HEkM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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