SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd89b10dce6a312619004fd16a531d5b403c52b43dd8a92349b46f92c269d1d1f' 
  AND token = 'FJanYvWCS1dD/uyjTugPJ+H36faXHT7Il0KL/s3HZik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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