SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a027a2c700e2a4f946bd383eee76d10797f13c5103014e8540ab2dd171273d2' 
  AND token = 'sl55ni8T5kezdAuFqnd5GRzb35zRGZqoTqmSgjbohtQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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