SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03bfa330dd999b197ce4bc7563e12955e79d8661e4b236b7445c3df1da9713ac' 
  AND token = 'Thce31JZ+QopGOVNdtj8gsBYlLW7AnCuw1DYTt3mZJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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