SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63ae51ba9dde48d2710879d721beea8394d899d729d9dcaac2ed15562a72786f' 
  AND token = 'Rp/4wdhp62UEhORjTNtzSggSvwMEnVEDKXKWO+4PTlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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