SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d5b1376bf48d38cc476f4d4adbf55928de1c0b76cfc6ee010f6f4272c34a31e' 
  AND token = 'v5TwgCxjDR7SeoPIJHM0UJ/YhRPlLVnE0mG1l+ljQWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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