SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01ee7324ef06257eb28664a8479d56185b656acf9f9549555ae673a9ebea1478' 
  AND token = '1zlboLnpCoatblpv9VkdawsxjxCfqY3nNytKhwlUzAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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