SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '688e45143b975b720e43592a699d78f6c3332a6bf041fff43d5931f84c4c0bb3' 
  AND token = 'aRTKuM2yUoI6qsPTc7JS3bPKjW6W4qh+9oNThlH+yBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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