SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5e36119850a23dbaf268789eb055c46696b25a7d4b5c42fd000d1a1dae824de' 
  AND token = 'jI3gTKBtvyaBi7AVFVV2wwSmHUG5vtVkRvGcZqEZ6us=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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