SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad36464b2ead9d72e1d34f214f4151956cfd41a354c709376612ebdeacc9841e' 
  AND token = 'XjmwEJHuOYdM0ZHa8s/R0OSzL9w5crXwBAdgTv8hhsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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