SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ead83cadfe87e85a3bd9e02ef3cdc04011c933edd83fcb18b7cdf6a8120620e7' 
  AND token = 'a8IHRY3WokNHRRSz64SYhDEtXowXlVUbSQ3BUhmzE+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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