SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f269e06fdaa4a1ea42b853bb1be7ba90ca4651f9726bb123799f2534eb31bedc' 
  AND token = 'vj8zFrSBtn2csD40HEsPRPmhDkRoxt1K0SLRzSAJoR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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