SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d82cfd68c2a566a6e94c335bdd184bde3a66889c6c00da26f24d7b29f897529' 
  AND token = 'L5UZHk9ljLGrs1xilJ2nFQ6f90S8YowJsMM0dn6Oqdw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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