SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '59e1bcfe9bc4de469d0184d64dbfcb4d809f2e138b6038a78075a5edf8f0876d' 
  AND token = '70dUcV0gezB9JWH3jEYGGXcQ6NCq67jPHi/HwNtQRUE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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