SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c3df933c24c5edb7e908d6c0cfd0e7b83f0dd4db41ea92b79f36e8057a73f8d1' 
  AND token = 'tBgeVkrs0Z6mUgVC8x/2Y8YljPEiuw2z1iLj5G6VajI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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