SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e3cab862e23b765dfa671d99f021d07ecefa6232fc42faa93fee893c6e7d23b' 
  AND token = 'KEzz1rVywVK2H8LkZIsuSygynBgW6AmqfBWXB/1lYgs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}