SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e11f94463764c7c214a444f99549e7b7df782fefaed860ac59fba71196308129' 
  AND token = 'f0ZvHoVIe4+EWVbk+dgGnB3FZvjjKn1zzwn5sF1YOZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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