SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f06ec087da56d0d7aec4d85e7f01749c5fb5837a59fadd0bc1352eeb7163a330' 
  AND token = 'YjAYh64e0DAdwcWOzU9QYjlkSvh+3qor8O9G2QBg/jI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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