SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e26a66f112e40448842d6d440f5ee0c1b9eaae14b184a88da4b4e622ee57b89' 
  AND token = 'Lx+M/QRbKDyiS1Mvd0jX6qrDBuKILhiDQNekHZpVbd0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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