SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1a167b147fa8bd278667906ccc61ddcab47cf9f6bf639b5bb04933d61d7422f' 
  AND token = '/+DV/JKYI+HcELJ5XoKz/gReBrn+x5/92qjpCARbO0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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