SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '507ed184fb42324cdeeb75d8ef5a79ac97a6314638f528b46a71c30fdc0a9be5' 
  AND token = 'A06srEAdPnfuwjeeSB6D+vQkyBUsNttYFlRsSlmI/dA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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