SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd9adaec0e7b9ae8c5c09880419741940569ebd2e0352db9332797a1d819ff59' 
  AND token = 'iK7hOm7VyZGZygD5AU5ti05ZwhG15UbDb8YgPkuetPM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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