SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2cdea1a5382e22393dc8ce6601f9ee44557bd86deccdffa660cb8afc46726c5b' 
  AND token = 'fLv4MVmhlSo7zb/Z0Zb6iTZOZy5YZnI5+43+PHk2z0o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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