SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64cd91287894515b36700595452e915f94898ad8816d0ea18c8db543f35c9462' 
  AND token = 'zBulSDTbb+h3m2RsLsXv4uHy6j3FyvM9V9Y9I0HIEsk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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