SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '236fd836566c63d3deec497780854a151ae7e82a8346570770be325e70970eee' 
  AND token = 'xftPaKlf2E90M6p+SalsrDYjLu5s3AVMZNOpfWukaSU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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