SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7400fc0cf38a7158f273bd3d842957b252517b9f64061b6161523e1bea1e3550' 
  AND token = 'k51VWWAh2IDP2uCM14VX/xvoP7o34NPBKrMm58Aqft4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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