SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86ee84de9aa827d245c97aaeef322fe0a2b1fcbb7e234c8eba13d1b98756512b' 
  AND token = '3Y3gTol8LKnqZrZZTKVvluymEQdbZd32q6J0T0b+8CI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}