SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e0556c1d5a440158a6eaaf04efa8b1206e4cd580b5a792795339c6a86578bc7' 
  AND token = 'YfBUrBwx1/7lOPJOlSDJ+zX1WgI5679G1qKSvrVnoNs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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