SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4605027c7d79cb7f45e5f6e904669b79a9635afbe28ed7bae3c8422cbb744880' 
  AND token = 'F6U4OAaUBIFPeI5BR5LzpH/RiwyZnwqB1xQnh+8LjQQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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