SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '869ad29e62f6dd1fb3e94576c388105f7da75b9397072b4483cf3c069d09361e' 
  AND token = 'M4GVIA2JIliRNS+VHsnarHz6L+esZpVYz0VzxNuqqK0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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