SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '513e5475470148a21cf381ca33b6ff100aec608ca24d4cc39aaa2b891b210c17' 
  AND token = 'kJbdCyYhctNHLGJVDUrC53X0vRa5YUMqgcTbmbhZIgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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