SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ae2bc7be46d929f50f691e988019aa7009e158cfb95f62b961cd402effe0816' 
  AND token = 'YEJJLI+JocJFhJNZuT4CDx98FWxaKm/BeXagwVh2fgw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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