SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '016900438e110f3f3e5e258d3b729910ca5b5b1e77aa5574a1b5f514a8a0ecb6' 
  AND token = 'EMY9rT6DCYZXGjb+skCJIw41hoNohui8HiW3iTmWqfk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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