SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5df2d816ee5f36121b34cdccf0c34818ad9742df763df828f24881bfc8cfaa92' 
  AND token = 'KUQHIz1suMz7KHnAYz38X+fiTBqzgVhSGGwD6JJwy8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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