SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '448932080779f7048eb0db227c0822512072ea14aea8b06522c560daa59eb1c8' 
  AND token = 'yPjGIQyISjneeWi6U2dsPuD3yqlozTMPgyUeG7T8yhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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