SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a34e2c19143625571b5dafbb091db39da18fcba2b8abf71d40fbd7849468f38e' 
  AND token = 'xYp4OOOgLcYBnIFL3wn18VlTmNmtJIoFF3e8Kzlgn9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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