SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ad701ec887de01f999269e51f2541f58326546dc44b01ca7f53d5bebd5db172' 
  AND token = '8Au2TU11KwBcQ1ewfmu+M5QHTJo7Yq5HOZtL/N2O9x4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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