SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ad40c202e95b39e5e36b249e1d60edf12b631c7158b81becb106b056ba5379f' 
  AND token = 'P24Et6RzNZFkPVPrYu/SFc3kmdCT4SFTvtKhRVvn4zA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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