SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98ae094a500ae541c7eb1597d43d8b47f5fa00abe2989aa36b2e332e69f119ed' 
  AND token = 'YOsoJpDxsQw9euM0k7pIGkO86UYLStnKCpIxBkb17ck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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