SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c5709c4f3823b17d6efb034ea3152f382b443b1eed81f701064886291a415dc' 
  AND token = '3BX6g0qqQOubDZzOA8nue7Vitd1GjE4y6wjbewUs0GQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}