SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a91779c30128c3647305c1bc866a9e7df82772e01c86ff62f88d8b9b7df72778' 
  AND token = 'n0uVYKL0nYyXUa+GVrScAxQuXOgItd7utYlwqlOuev8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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