SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bae9a723d33b20c7cdf03a884e82b2ab2d393d9590bfbcb6d9334b18ba528167' 
  AND token = 'M2xA9uPFvK5dRGmAXlnYnPTHzEhBKm1yk7lFuTlFlvc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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