SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f3d99e2b960d099c78de16dcbc24f290856c3395b988fed57e6f9d873f208c5' 
  AND token = 'ZrFM0FQfAb5Irv7nKtBhi0FlxYFZXUctu+seO97VOFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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