SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9747851e9a364617a6c091b182ac5cde96aa8efafca52e80f5e69542ca7f0a1a' 
  AND token = 'qCEIy6Kp16uDjkzWzvoTzy3A3uQareBK7t1QhvSNluA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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