SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bbb4466a5c61bf61d74daaf8d56ed9cde7d5e0de9efab0c715ddbd84330a077' 
  AND token = 'vF8XbjxtB5TkA3AmW1igJ1i/Cyr0CP9iksigoaeyM40=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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