SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26f512a930cc0b3cd6e792dd7e09e0f97f3e9dfec3c1de679135d6bd508fbcec' 
  AND token = 'LNjE0qjvkFdZLGDXoLxb9T8LYXKKYwlRh354WpKDnX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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