SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c0cd09a807ea093dd2aa4d25419145bf81c6213b421edb1ab7cf15d02a10ce8' 
  AND token = 'n5U1xq54WWNf/iz4U0I/Yupy8WAHkdaZQKNOmez0jWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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