SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc153de90cf450e1e76024d49bfe819830aa84bee111ceb96226ba8e73325a28' 
  AND token = 'UG+63dtuaAZGWuZSuX4ekafNxghHTSf9RbuQv4vYC9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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