SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c3de6cb56551872742734e7db95127d4cbc72fa37512bfea2ee3cdaf0311909' 
  AND token = 'nCHJoM/NwdWfHNGgqD8aUFtw99yzligE3k8isUnjDsQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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