SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9ca9b2188178da86d1cc5a94c3a8c89f55e96540f4114abb9ddcb66f8a5b5057' 
  AND token = '1VdAyKbdxQ13NF4wAwlHlTVzt2uoyafyCP2+5XhAhq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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