SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '579cbe06391602cc2ecb69d41aead29819285959e9a9c9b3aa48be66b581d6ea' 
  AND token = 'F3F12ls2dFqcHaAMq+cAT9qIgE+LxDAPrnX9GZ7/jT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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