SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '42599f022b23f0e06ebf2fa891f34e3ec463cc0562fb1f425c97e9cfe108f04d' 
  AND token = 'FUhkV/GtF5Yzq/3mta4PDesKtna+AU1ioxfy+Fa7yCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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