SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82dbaf013b638b9958c58eb3ae3524cb2bf681db84b7e151c57b91986b2f4e36' 
  AND token = 'aWuhVG6z5pPyK9CuWoYs0CyCqFq9qDiV/NWKZsDLOCc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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