SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3858d3bc7acf87e487d8bb0a376cfb63ec94328fad84b1f5d517aee6fc533fb8' 
  AND token = '3M9AP7Tv1wmznWoAIDkRmMldaibdDFrN0xINtF6krDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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