SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fb47229ec77faa9a7fabe7ff3ab88f0ca0f7fc87aa0beedabcf2f63d6bd7482' 
  AND token = 'PWQMNVVPRaXqnTOCPmWhqbEIXjF0y339q8tbaNkizXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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