Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f4fe950366755d6644347d4dc9d61675e6efa18588797118c24754126d544e9d' 
  AND token = '6s3kpTE1/rDo8wirZmu0kGYGapvQbNDgYap21L0mzGk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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