SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58390301242e9c9269afc40f355b3459bb5091166973bbfb2ef03286044660c1' 
  AND token = 'xLEYVmzs2zXNVrzq8xlPCtUQmjYhFaOHh4WHC/q1zBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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