SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '634b2418a15e18dd01b179bcc6b7032c59eb2ae4c4fec95f8c7df941a339c27a' 
  AND token = '09yqpnwRx+7QeCVHz0mhB4BgS4RoOXg9LKlN1DiE5eM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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