SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c8192b46a7f8c04cbcea812eed625abbe1f99511fe3ded0b2ab96dda847cca5' 
  AND token = 'Nr0AhZYawCLKyb6vhc0i6c2lDeCbglaLI7cV53yrMGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}