SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92b3d6a96e1a43e5f42c56f5d067d276510b1cded3e47b11199dd80e32e2762b' 
  AND token = 'H5T2FKYYzhWg6Mn8ej/k7EhKgEJlZOqON4ympxbDbFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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