SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37d4c03d752290836f33e45ba720dd1aa425ef468c981014213d3dc130bc66f3' 
  AND token = 'wwzWnWlbFKFJLuEypffTD7j+mVzR5tJxiv6AGx6LnuA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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