SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '845f48cc909fd54bcd331d4037f7148f0df5b8e6baf2faf8936812956a46e075' 
  AND token = 'O2ZaXVGYL+VUEfAfkMgrl04K/VKrz2fAmQJ47jHmwBw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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