SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e09604df093d72e5b7ca3cafb5890b3f85fe987c1c74cfca782a12b40c8c963' 
  AND token = 'ZXqdd5GIXDXu9W+MVL5r5XR/aJhA/JyvFb4v4uzg5/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}