SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc87976e2bb23f796b616db06620e7cdc0dc531858ab95e7a3c694e334b724a8' 
  AND token = 'YsHFsWy/FLrxQz7buUHMkchwLas+hLFe5n/cqVf9Elc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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