SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dcc718924bb296551b52ea075e03957cd2aba500f24785971cb255cc6c8233bc' 
  AND token = 'U9HJmIVzltFwPzPuPLpn9fzLzc+n3XmMGlKJUnc/7hs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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