Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '999ce234ea6599bf87a51f2e6331b03ae7b28eac21ab523199cebd9fd6efa2c3' 
  AND token = '88jty2uJEe6pfg6Fi4Tbboq6aVhNLK89TCXY49d0Un8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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