SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f25484eb774956c5ab6e7e77f871f33a10104029e5974c534f79b1f8f38dac14' 
  AND token = 'D6ez6QPJ5qox4jd333guAMa1ZeBnduokTbJtMGcMNwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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