SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2008ef6bb73102c799c8909bbacc25037b7e22cb7e33bfae774e5830ca771a4a' 
  AND token = 'aZTkFOsu28jUIxBK2CAz5uOmgAuPfSHvTn9jfrLAqc8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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