SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '652eb8f5eef9141d81fb6c86d9200ebbc286c218e5ecd0230c21660a07784cf0' 
  AND token = 'GnFcaIPqHtjZZUoYvJsJNHajJAWgfWEBv2K6kO0yFy0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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