SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7624ac14ada5010b8951bfa16852af68920df37ba227c32a3c770aac8e4cb14' 
  AND token = 'BhPkJtmVsjRILsoAigQNjvTDnHlTJ0qXTrb5QRIp2b0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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