SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '13ab6f2b26c436f28e4640a3bb75ee54f2c84f745a0234c698309f715af61ad6' 
  AND token = 'vzuFmIaN17hMeKXhKCjWPpZWddo3lac53bQ8iyzkbiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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