SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a41fb93f26acede4683a8a7557c79835ba79671e793394e176c09ad84e75d0e' 
  AND token = '9CAigNjqredDLzRYq/xY1X7vccwjfzLCRzdBtuqPjdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}