SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54e2705d678472a9ffa9b56fa74a89a3ad443a004d315e45cb64a9a7726fa1b8' 
  AND token = 'sBP6Bh3uEPcP/2o9w70+9NyfKxGmol44egmSe4diG+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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