SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1be2cd5da14e122be4e135e2cc47bd0ff88697b39ec8037f1397aed9ae25aa8c' 
  AND token = 'dcQ5v7iKviZjgznPJxhC1qrSRo50R9MANxvN8+QuQzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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