SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ba7e16797737c50a2919db78c66fb59f72954878f13c44ba78f7c6963bc6730d' 
  AND token = '+/JHXzPldC5LE0dXFhrZ/MCe39g/UCAbJojSdRBK2s4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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