SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '137a9cc46539e34cecbe5e69e875799c083e255f0ef58c34752ef9d494671126' 
  AND token = '91850B5DInPC3v3LLmW/p6Bfi7zQGZ/AQj/gam4U3mQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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