SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd07f7307365bf503dc809c66a5975dcd49103a9e331bfe94c296f4c0f156ad03' 
  AND token = 'g2MjeoHqrTvXqO9Xz20rTgUuAIFxcxf10henec2zGBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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