SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5719ae27cb978f1f5867582ef971e1654a3d74cd6d9e61463e9b134b3222f57' 
  AND token = 'ICdhXzCwWtTG9h0j2u5qob58DqzKIU8Qw7NH6aHARiY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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