SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ab8da60650c31e33e753581d5c8e7df92fbacce0f5588c5542fffb84af0464de' 
  AND token = 'DnAK+1cHJ42xHqLVJdIWtFKf+mo8QUBHbzJJb4Dpllo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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