SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '092cfdec940f583778a228edbd0ce28e36bbec3c2b6bd395540547b1ad848bd0' 
  AND token = 'zcit6uaWO2o7LOk7tdfucasP1890Yxd1mWu06qHTA5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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