SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ebf1d7b55f0268207bc4b1504ff85161e4e7c65dc37038087dfb5c6ef547bb0' 
  AND token = 'Mr2XYhgnzfobRYxpvwprJDn4x5HcSWVZcY+4OgJKxyI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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