SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cdb5c6e592b91df2e662f53c277dbc2e724c5f6954e9212b0d77a86451e5f16' 
  AND token = 'l9YsA0saON8pW7EE37YoUyxrfXvMp46OXFuKPeVoUuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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