SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8afb60e911c74b1fed613a61af02e1c04b081d4f0732a378019aa5cfcf3b2b11' 
  AND token = 'jkvFA9Np6J6t18zKSqAltq5F8QueglmZUYlLPVxcTKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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