SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6db6fbfea42b74a543f7eca8d429e9f46ed6efd83a7ef619b2918c71ea0c9152' 
  AND token = '7XSjpHCey0AAMPded3b+R0kNlwmdtRVYVrvAqqMSjoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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