SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f72059b59217454819ce68609cf7f8c9be42fda80fe2fa15fe3f690138970ac5' 
  AND token = 'qNst9ugL7gFbx/8GomdlqMsX3LbO5ThqTEkz/2Ie+N0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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