SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cab0dc4b54498724a12e2d4df848c557318800af82579b8d0b9d0eb8103aab1d' 
  AND token = 'dY3EwNJ7ZQCtnR91F7VSoosNNpDKyikp18oajvdoQyU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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