SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2e239f55f252de10b198a23f2b97acc075fd24cf9c58e1d1916d37c122052cd' 
  AND token = 'tXzenI/Ak0bt5d1IiKZzrMR0BhGNoJAJBuNsYLa8xo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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