SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'be619d2fefa919a61c6c9494883b65dbb6423101207163d15f1a406ad2c16b44' 
  AND token = '3wkpVdOY+W/0mHrNjAcGLGrA0OLs7Btue4p77lkzVZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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