SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a4dc4af8e87736d8ba84fd3292255f43ee689685eba5f10b0c1b848047a8694' 
  AND token = 'm2CAsrmqBK358/9hGALxhPwLlumzgwtPGEujDHAqnrI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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