Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1664a0ecb81d491e40592be20f1f808e290df799ff63a8b02b314638321d1834' 
  AND token = 'Lkc+n//isdzfhRw+IsWmACuy2bYPrfZEWCneW2YlImE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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