SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ebd5baf4989d2096bcfaa3e42ae14c73ef645955f53056936374581ae82a4e1' 
  AND token = 'iLRybrWfwGGQWoK6Le2tvYiOj2ZCaKfvXKZwmM016wQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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