SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f67310bc57a4a38125e3c63c8033645fbc51c93fc323a73268be54417bfc283f' 
  AND token = 'AZHKYoSF5LYOukobIHFoWqf93T/+vOxMxK2mW3mmVWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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