SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'beb8b006368fe11e2e5a485f9ae23de9de708d48684f0913babd07f64737fd77' 
  AND token = 'LTBpxj/GGGGVI623QJTqS+xwttoMYd/33K+LBlBoQU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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