SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89f64eaa97b60d0331596095b5b5d994fbdd7c98c4a5345ceabb8a3466bbe31d' 
  AND token = 'IhsfCX1JHNZlvrdn2tb7sNKA2nJevHmSJmNK7YFuhIg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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