SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26a268e773062cfe3b4f77839913949f69ed823c6880468b7c1fbe784bfe00f4' 
  AND token = 'l9pVInKlmJOPYoXKyhsT/qLP1DWT4d4zohWpcq2kqRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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