SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5905c43142d86adbbdd37495c1042f3554cd6ce21d07d266889f903b0d942fe3' 
  AND token = 'Amg1DvXBG4yxqw8Q1yDzQ+uTuMTkXi4XmQVGyPD7sVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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