SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ffbd69867c24eb4d84433ef58e072a658c0628a9fbcba7e26c53774a8a4a95d' 
  AND token = 'Vm/vy3PI1wAwtLSTsqMdTIOFQhVWzavwRPHUXCuWpPA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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