SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '252961414d62504cb5f409e2f96f061d4b75d2b4602c649b8b8867b4cd5fb035' 
  AND token = 'pqWxVVJ9AloL0mEM3NeB+jVZnEg/P/mZ6sCThDcJ5Hg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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