SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45dd5e46b5f6e5ae83686d576639842324c06bdb73ec9a81d6882fefc688fa02' 
  AND token = 'Za9z/taA+IqLEQAGzIl1mCGXhjWQLJ/B0hAZKieEB/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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