SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a2fd2e84573f68004db7f4152a1b31ed2084a25c23f2749d44e8ddbbe39e256' 
  AND token = '24ZZGwRjcRvheWgTzZLfG3kK/1g5UfBqOYF8dV6u4Vo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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