SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '967e3c153213a89e58eac16e715ab86d87f9bc22463904cdd589251553a4f1d2' 
  AND token = 'XzElB+Or8HrfCyt7awT/DQ2/kwzS1jwTf+2DXS/KfXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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