SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69293e5d2a17a7650eb496ef8f5f56701e980e0163e4bf14082efbd1c83d769f' 
  AND token = 'IFuszjGW4QNlEaim35KLqvUOpMIK34ZTJxQZEgg8SzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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