SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae6349aa8f7d25ea33bbc4e82b63cb6bee273399a8794d34093efcdd81065746' 
  AND token = 'FUfZ5zTpqmkavmLGL2+C9sQzMlYK6FKNePczgjSJ48M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}