SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ebfdc243ececf1953829b5c59a274a265ad4cff3d7668718485e0bbb663bbab' 
  AND token = 'Qz/O/akliQJWG4qN5KUVUY2jSxeiN4xuJbkz+zIYamY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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