SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09f826663424521a4f1c2c675424135c5a4c11211e582467bb3c2094a6efe9fe' 
  AND token = 'YE9TQj1mvNvkeFHYlzgfGZzgPMoe+vi2NdaJte3zBEI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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