SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5741e5f9b2c80e138cf539f8550461f66cd713a692b40fdd04656f59bd6fa3f4' 
  AND token = 'dwVR9aulzAGfDQucbmLfce5ZjbSlTmpbrJRpOtIH5VQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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