SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '741231667fd4161e9f59b4a05fe7fc810d12bfcc4853fa38d292c1b29dccdfad' 
  AND token = '2A1l8zYrSNYGJ2know6QbiCpjcrqyrNAx3hUsD6J8A0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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