SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '15f665967717a122f7c84c78003baf753dd481e78e9f51de09da118e171d9910' 
  AND token = 'reDLQejEIfPKIxGRK4r+sVY1KFiG5CEIz7GR4KvNf9E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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