SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f654c09d06a0b102dfc164e4477c498442bea64effdff172ec9ddf9e643246dd' 
  AND token = 'FWqiu6bFQ5sSEM8WWK3v+xvfAKC87qSWYlJTaN139Fw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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