SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '992105ddfef164e482463294ec39af5ab686e1f272bc0124f68f74e791f7d383' 
  AND token = '4gUcqi/TGlgtu09eP8zdwH1vZJwV8dTVzlxV6ilo7ss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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