SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69f94721c6588a8a205ca22964ebd0d1e03cb758dca2ea3c3213ccb0be3b4679' 
  AND token = 'T3losJ1oWaujssxmCVptJV31wtW5SO7ULdkf0YGzXbA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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