SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2828ad90df8524b56b5d0293b3628857001d589e76555724fcaa527e1a60a11f' 
  AND token = 'zRwZTBK9FPLGZs0jSAe2nr1ksTFo5vmXyhXw/3hjGLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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