SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bdee30acea2e1dceb64728eb108c03191c6d157da8935f9508be8985e3c665c' 
  AND token = 'VXsdeUNxsgz8XeYh/05wSAehJz8A92032DjxaSGYqoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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