SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af29d3a66cc8f2f486c559663ed5efa2cd8aa163f1b212b200fa5c9b831e0f7c' 
  AND token = 'HcKjuvv0rwStoOypCqzivBlmRVvuUUCjFz3wdGChMDc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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