SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '338b5c638a7a03dd9fe0553e6b861f87ced48001c9fc58f009dc4f6d2797f7bc' 
  AND token = 'BJJQre6rnS9KKbQe8y83k/092Gzy9GJ2p95PIXYsqws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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