SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52154aa0ed0e5d7c4d6089603972c79c5aee8118213b4280f530a90cc8de4802' 
  AND token = 'Yd5VZld41LMNNSaYNUcxWwapKbtHJsbDf6bmjnXtCTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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