SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9c409663e7da5829d095fd80419de92ad49225c678195b6e24d234ad8ac12fa5' 
  AND token = 'G93dgEweu1QszVKXUO5imInp04QmYajIV9O54wm+5y8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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