SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37989be4a9886707bb6a1f4e16dfcff00159c1855b376d3f2448de61a955174d' 
  AND token = 'LzNRbLN5umI3rWiddpnPQBN/ItoziUbST39OzFhgQmE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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