SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'da6080c10ecae6bb2b72492c590699536729461cfc18468161eaff6d8180d0bd' 
  AND token = '++xqCBeynIlO1byUKN/HQEPHY8Bz3UPylZhm+wMoivE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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