SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d65d1e0ca232d31c96be3d57cd872bb637c5e9b8b5cbe28273b56bc869cbf47' 
  AND token = 'hV/RK3jXvE0TyMon7xoHUSTIKDWMMLM9PMOiFy5nPyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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