SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2bec4147fa354c10def92ec62c848bc4b8ea8c9e590995b53ce67fc56f1d12c8' 
  AND token = 'rOju6C9UHMrrxG6qYObS8rITWwmNOjwlrA+5LmyNy40=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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