SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf837a7f93b3b0bc483310d48ea809c8605e2374b00f3fc09e92ce17ea909fbf' 
  AND token = 'jdIUTFHrMJbuQxBsTNihD5Uj3xmPzZp+ZAEfeAWJB0M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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