SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48eef989e2537c8febd736c9123808d974719fdd373cf039d7fc7fe0ec77c8a4' 
  AND token = 'O74cip6rXXg5VIe8ElMq52AQAVcFRaYFKCrAG7NTvUg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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