SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c8c33ea55bcecf49f4b1660ea4da0cfdadf1cb3f2673d653b2d097a24fe23f1' 
  AND token = 'T3zyiRYRkvasglWUVcZjWqATqeHhi89NzxKHUTnZfts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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