SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a023ceb5d6e273905b18799e460f34cf5b468f1436e10e1c74657e85c6b69d59' 
  AND token = 'aM35FQwqSf4l+T5HkwVRi+THsDaQsXFV0gdUlgWXU0k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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