SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8ba308ad7c13c28f96bc3ea5dd76474a85a6ad6516eec6b8ff4187c2162927b' 
  AND token = 'zv1XsEZ7FQ3igE/kHHGZRmBbY10CDrzVjsrgB2Y7YQ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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