SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d5048ab0eb552355259b780e4f84e73aa935fa5548b27d0e2f2b3879cb2f16b' 
  AND token = 'B0cAwi5nePJCwGWnbQRFs+D7K6H5xb+adwMZ1YoMIys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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