SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1080523b89f4fdb953363c9f24d33b6ff548917674151e5fd2d74948716c821f' 
  AND token = 'cgjWF2txqr7Hrt/+0qD8ZvfGR1D09qKRWK6XlOgVPHI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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