SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e8361d0e282b5d6856d673a8478d0a19cc991555982ed2559e2796ffe36f09c' 
  AND token = 'IMcc6IqrM4elOTM7fu7B6A8K8/+6/Ow8HvB+F7GT5jM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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