SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '389f3a2f9236614a0d8cb774bd905a6c86d00163005ed70bb15cb81b06b62914' 
  AND token = '4CIDXz8yCpf7WT3HHL/jYhq0ssBRE5thOTiWXO2NXwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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