SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f076fe9585f78450e4130e1c5499ffb0822e8b3cd921ca62f1d9fbd9a28d5479' 
  AND token = 'kyi9xWIj4iZo6YR9vfpqFXYxOvha/QDBfvzAyxUo7X8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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