SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2cc4237555e334ef9f19f4d74c8555a68f35dbe74818735f68c02561af9d6498' 
  AND token = 'Z0ImrXOKSv3LDRhjL/K90+FJugH9RMCR8SYUDwGX1co=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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