SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3676da85c4f964654d7d1dc38ca48885a90d0bed9ab91153b11984b4d6a91d19' 
  AND token = 'oLD9eZDdfoBh7urMtLTDCVWpy/zoRzx5oexspmKGLNI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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