SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2322eac0739b1862cf26bea47725d50e1be5b9af006819d041381815764315cb' 
  AND token = 'VYOfr9vkbuGKnU/xzqgLXdkXSDtCzGDB5Dt/5+gzafM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}