SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e07430360a7c31a7970224d275929d92a92b57f01d5f93edc5a47d259673d86d' 
  AND token = 'hp5julNl/xUWeM2ZdnY5Mtyh0AEvlM73q6uYgBQ/yD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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