SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47ee042cb812b5f2032dd0f15580cc9f57d6d67a44ae03ac12344f9e325b7648' 
  AND token = 'jGbVC/8Oa6Xp1qLw51Iyt/O9KG9spxqLYtN8hQW1f/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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