SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41ac5ab284abf8dd3159c0ef0a4cc23cc80e6e27d25091f9e488452737380b22' 
  AND token = 'mWHgTIHYMNY+eziGFAH6cpJlxHZ79iYTSaWfpVF3olI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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