SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa6b80ba07a609bf877eeb655b8a6306fa178dd66048049b5f82bb9af40d9b36' 
  AND token = 'v5VBd8iAF4WhGFhwk17U8RxfDANaguz7VrKECLggb3k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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