Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e57cef5a3271b335bf5dc31fd92980e04948d8af628d73f4649ffde9496809d' 
  AND token = 'C4LAkfzTawJ9eleDjHuVLB+gsVlWsu1f2/pVpk+uIcI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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