SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06667c3becf2212328ddb98b65ca359d9f8f8821c2fe2af0e028e440794ccf18' 
  AND token = 'qTZlVdzVtbFZwQq9BeffRfBYy0DvqR51GquGj8eHEyI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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