SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1dad89356228d7664b59817b3284b7d12d086f4f158ab4b9694d064334fea60c' 
  AND token = 'Tr1XaudxSjQHXb8jgoq7ULG45DzGoa4mKqLmGqzuwIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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