SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f6133877ac1b68e3895bacbe3456aca03d8ccde85b677903fb3eb488e44d9af' 
  AND token = 'EloYSNWAXvI5pJaOdki9LweQ6JCWcdl7K8lGJYeafpc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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