SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a74a39c5ca815b6157028ee3b372b5cce01366be461e4ba69b31e24eb4f1551' 
  AND token = '/pub+0upAOjYxu2SA2HGCvSeWHxaPjSWIsnbNvdlD7c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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