SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '192038b3aa24a867936606f334189bf5e2b38f8d1c69a4020e82b0f04550b7a9' 
  AND token = '9PGFxX92jbtORVTQj9IlpTUGqhUjbu3MrurgmTSGL6A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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