SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2fc48ea8c49fadcba01bcc25e924029ff8a48bd56dee2eb36db3982174de77e' 
  AND token = 'swSZ9BbcgaqWSYfxoLbPEzdKQJRkiEmoskcKE9h1WgA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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