SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2bb22890fbb2a7cb759322f30b8bebadab7c7b8c938c3ae06b4f90959b0bf7b' 
  AND token = 'ksSymWgUXsD/qD8oQQkj8yJbhLdc9OzcZ5bDOXpKrJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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