SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '028f80db0137c6253e761c7f6a1428fbbbf6afb8fc1f86579a6b63dec9a39441' 
  AND token = '95Yp0OH5B9rL2zEEWjUOxIlt27ukN4WH0uWt/5SQBoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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