SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3254190c52d713c79676babce8b0ffb014996ae618886c7e3dff7d78f7b2f92b' 
  AND token = 'JXblCwNW8k3QvA4qIHdCTokHhnZTgx6L3iVI7sDMYQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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