SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40ab968d0718b612974d7bc1f611f708039d9cbbaa71d5870d04462a481f0fc8' 
  AND token = '5ccskv6T2jGVk1y8EW6Hoi/dVH1ES/BHDs5j1imB8cI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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