SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab424aa6a5aea599b1c96353cb514c64bf323826b1e7e1ebaed361c10af7a8b2' 
  AND token = 'Cqx0gbyENEcelWCBbjUIeNHIcHT+TyPCkYkS/DpWhXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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