SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bba52b2ee0dfe1a769f2a4233414e4c1430350c16a6ac6ff89e5c1564dfaef61' 
  AND token = 'UNLVvstcGZQ71IwljkekFa6RcKIhTONBCUNNl3iHCpo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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