SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99eda003fdc58229b15ad56c20bf0278814f835810e8b294fe067c5cc42afed6' 
  AND token = 'D18qqUIxd6KYWIJlByI3SjYZ2lvx4Y9H8KajrnZ+GjE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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