SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1027c49184d05175caf421d8461b6934f55fadb7167a528129cfbd9b3957fb15' 
  AND token = '0NgiyJXDYA9tOlp49tdiRHdgPMvzRhhpztYKM7pcaG4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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