SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '1f3353ca8dadd14de1e62ff451fc3275d5accc1435ba54ca304e1d7560983759' 
  AND token = 'H6jVA6DPWuZ4SJjKUAH/fUFzGpBVjNqfOCPBVyIcLQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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