SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ea1ad28bdd4492b66f13c1ff4cc0ff72551f4636a4350ccf55b8af61bb2c9c2' 
  AND token = 'Adp8Vw5+0WCyE6ar9FpnKmQHrYLpUZtEOyKBMqvGp70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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