SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eabf76544cdd1fbe3b8f928c12ca798779ed65b3abf51b35a78b6952f566bb76' 
  AND token = 'DiNxYd5avJQGintdBC2g6xZz/6Ji9scadwkKRqOtVgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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