SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfcbfd15e951ac072ffbc92bbd581b8a88d8b18df0b6337c71a45035235192b6' 
  AND token = 'pX034DQrEQ/Kw0mMabvr//UJChzmMdvcdc/35xoGWFI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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