SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9476f9a852ec6e8e994b3698ac4d1f57a346e3ce4f9107dc2ebd380f80746f20' 
  AND token = 'AVXszZ/vqeK9Lg0DsQNhYCmcG+uFZ36qSSkIn7ufQYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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