SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3387653626c0207ff195329a7ec0d484c67bd6cb790c54dbb8a4f9c70b290c95' 
  AND token = 'HafEXHnh8ip/7SoqJ4Wv4K24mG+Bp+zMULk0l/6pSFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}