SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6d9e4adf2948ac37c0dff6e8a9b2c241c40856645b2f712cd31ec6d2f52ad235' 
  AND token = 'Z4rZVMVXKMJQVuJ6jB3Aewq+phecQMAzqAfsFquSFOY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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