SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09e569ad899d1e976579ba9790c0a2d014172acedfe8c87248cf48c3ec747d24' 
  AND token = '8QA4s0BjzMXrXZLFvaOWyYpEFEIx2tImLSJnbibkoAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00137

JSON explain

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