SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ebe911d499201d9adba7b8210e3c254cb2030256449137a08353d58e3a46969' 
  AND token = 'WW+cGvqtLxcdVdPG7VCvALzgOqzQKqy3nU9+Nlj6F4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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