SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '899ede4f414f60affe64f7e8a0837a7fc1bb52ea6558c2b759cf335608ead2bf' 
  AND token = 'xvHeQbQhiPhIzL56ZOBnFNA4lDkJmDH//t0PsTNm4vY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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