SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ddc249078a43062e6c83464b67e859088bb10a2ac33f40f74c11344942dc31f5' 
  AND token = 'LJHzxnK3sSZ6YlhkMycfQA7kXPblqJSqwzsSPTR3C3Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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