SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae65a7c16cd969814d522669bef3800442253bdc4952443218435896033f4fc1' 
  AND token = 'xwvOgrCuSV2HCKLyKrPLZK+5yr9K9RWR9e2I4dDvNLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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