SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4480da69d5bf1ace71249a7ed9ad85439904af28b7a12fae9364c1a341fdd58f' 
  AND token = 'GiRSMTIJta2noNQOIJmqLzFlMhsNSShJWrumjqoS+f0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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