SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '30b452e04c3d9f8f2f333779bafb5607798aed363c3562a8e35c042d0b26ab1d' 
  AND token = 'jM/vZV4842Pwl6xfsZu8b/5O6DHQ7aTKKKIhQTKcwo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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