SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65246939341245d41c8258b41cb8763c96f4d6c88f7aab128674494f33de73b3' 
  AND token = '+03e03CwXm9yJOrHPGeW5BffpMxTyJF3n2wtEpacqfk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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