SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e63aa1a7924211e094667c61e754c262afe3b6ef295c8d0fcec784e1468efafc' 
  AND token = 'vuJ/rG0k7UhqwlnDpEfOCW6PSwo6AyOzzjxV+pglIes=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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