SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e038a973857ffedb8e617669520039af8b2c2dfa2da246142f2d55a9bd315704' 
  AND token = 'jYjvofCpqTeMKaUTBZgHJNZjFcZ7tcy48e3QsdW14Ac=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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