SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '717a20c0794d9a2e5897ba2253e0715fbe936fedfd5bd804fcc7858e05482e78' 
  AND token = 'v6eAutC8Q8d8570qX5QphC4miMsK0kzN2dktKtndCAc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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