SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30d2b0d500587dd28ed0fb76fe9015695ada56da136835ce05710c6a174e7c2d' 
  AND token = 'z/F+tyVGwEU2jV5qBM4eUpfn2uHhZIJ8YQknhzJO3ew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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