SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4df007f9a82d63cacd55fc5ef6c58738f463fc60b6e51a2769ed8116004e8f7c' 
  AND token = 'jSI0gDFSkkCE1bv/VvbS7te9OiSyjMhMSvVVyMVzTbs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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