SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00fd1a37499a1d1a2f9e0a28eca2dc46745f16e9299429526003ce82179843af' 
  AND token = '/QT0jyPzjVp+HnBSlRudC4YB0QQeY8roZiNnsshTxjM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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