SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '810d5300f986692ae5590ecfe622157c98e6b2ebcbc02ab313149edb0922c735' 
  AND token = 'ws1TJAM0JY8XlRjydilgwNvKmLMdrAPnpHva8TIccbo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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