SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f46f67284d2425a008e9842d3d7eac07c36b7fe34a851bd30d11ed181499d59d' 
  AND token = '9Y3Vm9nKhst4/hLM9u2H9pQL5H7S1OxLRGtMLZMYSZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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