SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9dd480ab1928cfb98ab2664e7146597a005d7c4bf0d2718a22efabf944797c8' 
  AND token = 'C03eoHYetDayAESHk3BlfsURvTrTvINJVjuupFg3XtQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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