SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d8675ce9ac3a1b551ee43970e983fa9ec6c0e2f67a8ce638533cd5796a939e1' 
  AND token = 'iyJYoUPlVFHGdSyHsUlFOgUnSycUvH5J7ssWvV2lfFI=' 
  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"
    }
  }
}