SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0f246183b58321d2bc4bdc32bb231e53739804d8d7071bea6aa9df36775466c' 
  AND token = 'YnolxvZ7NODEuCBQcv7yuA9/mIZxJk5mWCVWczbzxwI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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