SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'dc214fe25b1f338bbad80950addf9c6ed79e1dd978b0742002ba46864e816a67' 
  AND token = 'kU/YqzXtSivxTWFmH7aOA9Nh1pdgdv7K/CEyYrNeSUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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