SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cfe5c78000bbb03704a2d95b88520e3773ef2e5a4dde107fecb947c417b85bef' 
  AND token = 'IaBlCZuv17fZokbPc6PfslavCtGYKonTzsMV65FnOUY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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