SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0314adb798c4bb73f33bc7e57622964d935b587b050d44baef814609f35a3962' 
  AND token = 'PiBmBUdFd+19zJEUgDksMPC8zF1Zw8XI+JY+kS2RNXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}