SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70be9f4a136b065de356f00ee1ae15cddf9f104276bf0d9c06557b4844377060' 
  AND token = 'I4uQW2+/PCZwVNaqjM+xzqmRDDy8y/yc5vYMyvc6qAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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