SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a00b375c7a1fa15d7e4f1a855ed1746a392980aa382b5f68758ae4637941ce19' 
  AND token = 'AMXO0xnNy3jUyt4Um6+oXNb9lADke8sJSJjz8eK7qdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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