SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4dd13bc0eb1b83f32ea7398596dbf5c5c63db31a656ea8b389e13c6d14cd8831' 
  AND token = 'h2bJNLVdsf2/PjpejF6i6rKyGkJPkEjoSAUA93CJ93c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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