SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0716f2929e594f0422f6641ff41e61ba39e8340655cf80abedd7d413d5085b46' 
  AND token = 'S8WO58zDKYZOUccKTJB/HWRB07UxGI3xl5GVblYesnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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