SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c28ec6976b27de801aac87bd154aa64f429cb66233f6b2021e3d276f06cc56ec' 
  AND token = 'NF1cc3r3eEzbMqWvCRHynPm+63yVzgC6ZolpbLJy0DE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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