SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65c2aa9781099b9eb3de7f43d99314792223b1828aec28bd812949d45e48514a' 
  AND token = 'EwY4gm64VGrpFN+uOhNKQynd/Qzw1vhl88K1JfwZSlo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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