SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7292c33be7d6d7e7443553809ff6cd8248bff9cd5f1370f6f92bd8180dd88f92' 
  AND token = '9XiBdsIJlxudDl/WXlxXphJ/yV18KWszz4r4l0QOz0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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