SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0280a67447e527a45432f845fbebaa64cdf7db3095b44fb80e344257785c577c' 
  AND token = 'rNQ4mgi4Iwdads/u6bySyf9D2g2V5POQSwuTDdLDccQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00070

JSON explain

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