SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47f8ca60e2160af37812c9b8d4a33add6904782006eabc5c9a4e29d26b4c0362' 
  AND token = 'wgbGVYvA0CLMuh/mdqKZhip1XVE8z6xS8eiFGW7hNaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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