SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41befc461eabc013d55b6dfd789b7c48cdd81edac60df0c6db2ce21208dc01c3' 
  AND token = 'X/BzyJmZL+m8jWUvwjCVkmQ9JWUOuCCjL3Ag3IqEBWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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