SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '767365f1e9b7451af17452af9d31a4d50c2fb157333dca555abfd6ab89bac868' 
  AND token = 'lbgvqIvPDX0Lg+7zHmaxLFdv34SABu1lYWTx2FevPSc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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