SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e8e417bdc45381134a71559d76e2e76486ac1f19acd238f11e2fbfeedb37722' 
  AND token = 'rMmHYJZ/aHm+Vz/bYWWho2EO0JFEVFJ48rw7JpFE7sc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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