SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b882ae7e15530ea5ad565a8b838c8b4f71c5d1bee0d78aeff92e0d8de775dd6' 
  AND token = 'IzYxahrHMDwx60x6M4QMIgECBJwYDMqokrCZPgEsqzA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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